A. Basic Support: This plan offers customer service for account and billing questions but does not include a dedicated, proactive concierge team.

B. Developer Support: This plan focuses on providing technical support to developers and does not include advanced account management features like a concierge.

C. Business Support: While offering more comprehensive support than the Developer plan, the Business Support plan does not include the dedicated Concierge Support Team.

1. AWS Support. (n.d.). AWS Support Plans. Amazon Web Services. Retrieved from https://aws.amazon.com/premiumsupport/plans/.

Reference Detail: On the "Compare AWS Support plans" feature comparison table, the row "Concierge Support Team" has a checkmark only for the "Enterprise On-Ramp" and "Enterprise" plans. The description for this feature states, "The Concierge Support team are AWS billing and account experts that specialize in working with enterprise accounts."

2. AWS Whitepapers & Guides. (2023, September). AWS Support User Guide. Amazon Web Services.

Reference Detail: In the section "AWS Support plans," the description for the Enterprise plan explicitly mentions the Concierge Team as a key feature for handling billing and account inquiries. It is not listed as a feature for Basic, Developer, or Business plans.

A. AWS Lambda is a serverless compute service that runs code in response to events. It is a component of serverless applications, not a tool to visually design them.

B. AWS Batch is a fully managed service for running large-scale batch computing jobs. It is not used for designing interactive or event-driven serverless applications.

D. AWS App Runner is a managed service for quickly deploying containerized web applications and APIs. It simplifies deployment but is not a visual design or composition tool.

1. AWS Application Composer Developer Guide: "AWS Application Composer is a visual builder that you can use to design and build serverless applications from multiple AWS services. With Application Composer, you can drag and drop AWS services onto a visual canvas to create your application architecture." (Source: AWS Application Composer Developer Guide, "What is AWS Application Composer?", Introduction section).

2. AWS Lambda Developer Guide: "AWS Lambda is a compute service that lets you run code without provisioning or managing servers. Lambda runs your code on a high-availability compute infrastructure and performs all of the administration of the compute resources..." (Source: AWS Lambda Developer Guide, "What is AWS Lambda?", Introduction section).

3. AWS Batch User Guide: "AWS Batch enables you to run batch computing workloads on the AWS Cloud. Batch computing is a common way for developers, scientists, and engineers to access large amounts of compute resources." (Source: AWS Batch User Guide, "What is AWS Batch?", Introduction section).

4. AWS App Runner Developer Guide: "AWS App Runner is an AWS service that provides a fast, simple, and cost-effective way to deploy from source code or a container image directly to a scalable and secure web application." (Source: AWS App Runner Developer Guide, "What is AWS App Runner?", Introduction section).

A. AWS Partner Solutions Finder is a directory to locate AWS Partners for consulting or technology services, not a direct software purchasing platform.

B. AWS Support Center is for obtaining technical assistance, managing support cases, and handling billing inquiries, not for procuring software.

C. AWS Management Console is the broad web interface for managing AWS services, whereas AWS Marketplace is the specific service within it for software procurement.

1. AWS Marketplace Documentation. (n.d.). What is AWS Marketplace? AWS. Retrieved from https://docs.aws.amazon.com/marketplace/latest/buyerguide/what-is-marketplace.html. In the introductory paragraph, it states, "AWS Marketplace is a curated digital catalog that you can use to find, buy, deploy, and manage third-party software, data, and services that you need to build solutions and run your businesses."

2. AWS Marketplace Documentation. (n.d.). Finding products. AWS Marketplace Buyer Guide. Retrieved from https://docs.aws.amazon.com/marketplace/latest/buyerguide/finding-products.html. This section details how customers can search for and discover software from independent software vendors.

3. AWS Partner Network Documentation. (n.d.). Find an AWS Partner. AWS. Retrieved from https://aws.amazon.com/partners/find/. This source describes the tool's function as helping customers find partners for specific business needs, which is distinct from a software marketplace.

A. Managing and encrypting application data is a customer responsibility. AWS provides the tools, but the customer implements and manages data security.

B. The customer is responsible for the guest operating system, including applying security patches and updates.

D. Configuring security groups, which act as a virtual firewall for instances, is a fundamental customer security responsibility.

1. AWS Documentation, "Shared Responsibility Model": This official page clearly outlines the division of responsibilities. The diagram under the "Shared Responsibility Model" section shows that AWS is responsible for the "Hardware" and "Software" of the "AWS Global Infrastructure," while the customer is responsible for "Operating system, network & firewall configuration" and "Client-side data encryption." This directly supports that AWS manages infrastructure devices (C) and the customer manages the other options (A, B, D).

Source: AWS Documentation, https://aws.amazon.com/compliance/shared-responsibility-model/

2. AWS Whitepaper, "AWS Security Pillar - AWS Well-Architected Framework": This whitepaper details the shared responsibility model. In the section "Shared Responsibility Model," it states, "AWS is responsible for protecting the infrastructure that runs all of the services offered in the AWS Cloud. This infrastructure is composed of the hardware, software, networking, and facilities that run AWS Cloud services." This confirms that infrastructure device configuration (C) is an AWS responsibility.

Source: AWS Well-Architected Framework, Security Pillar, Page 5, "Shared Responsibility Model" section.

3. Cornell University, CS 5412: Cloud Computing, Lecture 2: University courseware often clarifies these concepts. Materials for cloud computing courses explain that for IaaS (like EC2), the cloud provider (AWS) manages the physical layers up to the hypervisor. The user manages everything from the guest OS upwards. This aligns with AWS being responsible for the underlying infrastructure devices.

Source: Cornell University, Department of Computer Science, Course materials for CS 5412. (General reference to common academic curriculum on IaaS models).

A. How quickly an Amazon EC2 instance can be restarted relates to the availability and operational performance of a single resource, not the system's ability to scale capacity.

C. The maximum amount of RAM an Amazon EC2 instance can use is a static hardware specification of an instance type, not a dynamic characteristic of the cloud environment.

D. The pay-as-you-go billing model is a financial benefit enabled by elasticity, but it is not the definition of elasticity itself. Elasticity is the technical capability.

1. AWS Whitepaper, "Overview of Amazon Web Services" (July 2023): In the section "Six advantages of cloud computing," it states, "With cloud computing, you don’t have to provision resources up front to handle peak levels of business activity in the future. Instead, you provision the amount of resources that you actually need. You can scale these resources up or down to instantly grow and shrink capacity as your business needs change. This is known as elasticity." (p. 4). This directly supports options B and E.

2. AWS Well-Architected Framework, "Performance Efficiency Pillar" (July 2023): Under the principle "Democratize advanced technologies," it explains, "In the cloud, you can provision the amount of resources that you actually need... You can easily scale your resources up or down to meet demand without long delays or lead times." (p. 6). This highlights the ease of procurement (E) and scaling to meet demand (B).

3. AWS Cloud Practitioner Essentials, Digital Training: The module on "Cloud Concepts Overview" defines elasticity as the ability to "acquire resources as you need them and release resources when you no longer need them." This concept directly maps to procuring resources when needed (E) and rightsizing as demand shifts (B).

A. PostgreSQL on Amazon EC2: This option has the highest management overhead, as the user is responsible for all database administration, patching, and backups.

B. Amazon RDS for PostgreSQL: While a managed service, it requires provisioning a specific instance size that runs continuously, which is not cost-effective or optimal for infrequent use.

C. Amazon Aurora PostgreSQL-Compatible Edition: This is a provisioned service. It requires manual capacity management and runs 24/7, incurring higher costs and management effort for an infrequent workload compared to the serverless version.

1. Amazon Aurora User Guide, "Amazon Aurora Serverless v2": "Aurora Serverless v2 is ideal for a broad set of applications. For example, it's well-suited for applications that have infrequent or unpredictable workloads... With Aurora Serverless v2, you don't have to provision, scale, and manage any database servers." This directly supports the choice for infrequent workloads and least management overhead.

2. AWS Documentation, "Databases on AWS": This page outlines the spectrum of database services. It positions self-managed databases on Amazon EC2 as requiring the most customer management, while managed services like Amazon RDS and Amazon Aurora reduce that burden. Aurora Serverless is presented as the option that further minimizes management by automating scaling and capacity.

3. AWS Documentation, "Amazon RDS features": Under "Easy to Manage," the documentation states that RDS "reduces your administrative burden," but it still involves provisioning and managing DB instances. This contrasts with Aurora Serverless, which automates this process entirely.

4. AWS Documentation, "Best practices for running PostgreSQL on Amazon EC2": This guide details the user's responsibilities, including "installing and maintaining the PostgreSQL software," "configuring high availability and disaster recovery," and "managing backups." This confirms it is the highest-overhead option.

A. Classify data: Data classification is always the customer's responsibility, as they own the data and understand its sensitivity.

B. Configure access permissions: The customer is responsible for defining and configuring who can access their DynamoDB tables using AWS IAM policies and roles.

C. Manage encryption options: The customer is responsible for choosing and configuring encryption settings for their data, such as selecting AWS owned, AWS managed, or customer managed keys.

1. AWS Shared Responsibility Model Documentation: AWS is responsible for the "Software" components of its managed services, which includes the underlying systems for services like DynamoDB, and the "Hardware/AWS Global Infrastructure," which includes the physical servers and networking. The customer is responsible for "Customer Data" and "Identity & Access Management."

Source: AWS Compliance, "AWS Shared Responsibility Model." (aws.amazon.com/compliance/shared-responsibility-model/)

2. Amazon DynamoDB Developer Guide: The documentation explicitly states, "AWS is responsible for protecting the global infrastructure that runs all of the AWS Cloud... You are responsible for maintaining control over your data that is hosted on this infrastructure. This includes the security configuration controls you use for your DynamoDB resources." This confirms that infrastructure (E) is an AWS responsibility, while configuration (B, C) and data management (A) are customer responsibilities.

Source: AWS Documentation, "Security in Amazon DynamoDB," Shared Responsibility Model section. (docs.aws.amazon.com/amazondynamodb/latest/developerguide/security.html)

3. University Courseware: Reputable university courses on cloud computing reinforce this model. For instance, course materials often illustrate that for "abstracted services" like DynamoDB, AWS manages the infrastructure, OS, and platform, while the user manages access control and their data.

Source: Patterson, D. A., & Armbrust, M. (2017). CS 61C: Great Ideas in Computer Architecture (Machine Structures), Lecture 26: Cloud Computing. University of California, Berkeley. Slide 33, "AWS Shared Responsibility Model."

A. Amazon EC2 provides scalable virtual server compute capacity in the cloud. It is used to run the application, not to perform DNS routing.

B. Amazon VPC provides a logically isolated section of the AWS Cloud. It is a foundational networking service, not a public DNS service for routing users.

D. Amazon RDS is a managed service for relational databases. It is used for storing and managing application data, not for directing user traffic.

1. Amazon Route 53 Documentation: "Amazon Route 53 is a highly available and scalable cloud Domain Name System (DNS) web service. You can use Route 53 to perform three main functions in any combination: domain registration, DNS routing, and health checking."

Source: AWS Documentation, "What is Amazon Route 53?", Section: "Route 53 as a DNS service".

2. Overview of Amazon Web Services Whitepaper: "Amazon Route 53 provides a highly available and scalable Domain Name System (DNS)... It effectively connects user requests to infrastructure running in AWS—such as Amazon EC2 instances...—as well as to infrastructure outside of AWS."

Source: AWS Whitepapers, "Overview of Amazon Web Services", August 2022, Page 31.

3. Amazon EC2 Documentation: "Amazon Elastic Compute Cloud (Amazon EC2) provides scalable computing capacity in the Amazon Web Services (AWS) Cloud. Using Amazon EC2 eliminates your need to invest in hardware up front, so you can develop and deploy applications faster."

Source: AWS Documentation, "What is Amazon EC2?".

4. Amazon VPC Documentation: "Amazon Virtual Private Cloud (Amazon VPC) enables you to launch AWS resources into a virtual network that you've defined. This virtual network closely resembles a traditional network that you'd operate in your own data center..."

Source: AWS Documentation, "What is Amazon VPC?".

A. Physical connectivity among Availability Zones is part of the AWS Global Infrastructure, which AWS manages and maintains.

B. Network switch maintenance is a component of the physical data center infrastructure, for which AWS is solely responsible.

C. Hardware updates and firmware patches for the underlying physical servers are managed by AWS as part of their responsibility for the cloud infrastructure.

1. AWS Documentation, "Shared Responsibility Model": The official documentation clearly outlines the division of responsibilities. For IaaS services like Amazon EC2, the model shows that the customer is responsible for the "Guest Operating System (including updates and security patches)". AWS's responsibility ends at the hypervisor level.

Source: AWS Documentation, Shared Responsibility Model, aws.amazon.com/compliance/shared-responsibility-model/.

2. AWS Well-Architected Framework, Security Pillar (July 2023): This whitepaper reinforces the model. In the section "Understanding the shared responsibility model," it states, "For IaaS services, such as Amazon EC2, AWS manages the infrastructure... You are responsible for the guest operating system (including security patches and updates), any application software or utilities you install on the instances, and the configuration of the AWS-provided firewall (called a security group) on each instance."

Source: AWS Whitepaper, AWS Well-Architected Framework, Security Pillar, Page 6.

3. Amazon EC2 User Guide for Linux Instances, "Security and network concepts in Amazon EC2": The user guide specifies the customer's role in securing their instances. It states, "You are responsible for the security of your instances, including patching and maintaining the operating systems and applications, configuring the operating system firewall, and configuring the security groups and network ACLs."

Source: AWS Documentation, Amazon EC2 User Guide for Linux Instances, docs.aws.amazon.com/AWSEC2/latest/UserGuide/security-concepts.html.

B. VPC peering is used to connect two Amazon VPCs together, not an on-premises data center to the AWS Cloud.

C. AWS VPN establishes a secure connection over the public internet using IPsec tunnels, not a dedicated, private physical connection.

D. Amazon Route 53 is a scalable Domain Name System (DNS) web service used for domain registration and routing traffic to resources, not for establishing network connectivity.

1. AWS Direct Connect User Guide. (2023). What is AWS Direct Connect? Amazon Web Services. "AWS Direct Connect is a cloud service solution that makes it easy to establish a dedicated network connection from your premises to AWS."

2. AWS Site-to-Site VPN User Guide. (2023). What is AWS Site-to-Site VPN? Amazon Web Services. "AWS Site-to-Site VPN creates a secure connection between your data center or branch office and your AWS resources." This guide clarifies that the connection is made via IPsec tunnels over the internet.

3. Amazon VPC Peering Guide. (2023). What is VPC peering? Amazon Web Services. "A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them privately."

4. Amazon Route 53 Developer Guide. (2023). What is Amazon Route 53? Amazon Web Services. "Amazon Route 53 is a highly available and scalable cloud Domain Name System (DNS) web service."