Network Load Balancer:

Deploying a network load balancer ensures that incoming traffic is distributed across multiple web

servers, providing high availability and redundancy. This setup helps in managing traffic efficiently

and maintaining service uptime even if some servers fail (Option A).

Multiple Availability Zones:

Deploying web servers in multiple availability zones (AZs) enhances fault tolerance and availability. If

one AZ goes down, servers in other AZs can continue to handle the traffic, ensuring the web

application remains accessible (Option D).

Other Options Analysis:

Option B is incorrect because NAT Gateways are used to provide internet access to instances in

private subnets, not to make private addresses reachable from the internet.

Option C is not sufficient on its own for high availability. Adding a route to the default VPC route table

forwarding traffic to the internet gateway makes the VPC internet-accessible but does not ensure

high availability.

Reference:

AWS High Availability and Fault Tolerance: AWS High Availability

AWS Network Load Balancer: Network Load Balancer