NetApp Cloud Volumes Service (CVS) for Google Cloud is a fully managed, cloud-native file service that provides high-performance Network Attached Storage (NAS). It is specifically designed to support multiple file access protocols, including NFS (v3 and v4.1) and SMB. This allows diverse clients, such as Linux and Windows systems, to access the same shared dataset concurrently. Therefore, it is the ideal solution for a new application in Google Cloud that requires multi-protocol file access.

A. Google Cloud Storage: This is an object storage service. It does not natively provide file-level protocols like NFS or SMB for shared file system access.

B. NetApp Astra: This is an application-aware data management service for protecting, recovering, and migrating stateful Kubernetes applications, not a primary file storage service.

D. Google Cloud Spanner: This is a globally distributed, strongly consistent relational database service. It is not a file storage system and does not offer file protocols.

1. NetApp Cloud Volumes Service for Google Cloud Documentation: "Cloud Volumes Service for Google Cloud is a fully managed, cloud-native data service that provides NAS storage with advanced data management capabilities and support for NFS and SMB file shares."

Source: Google Cloud Documentation, "About NetApp Cloud Volumes Service for Google Cloud," Overview section.

2. NetApp Product Documentation: The documentation explicitly details the creation of volumes that support both NFS and SMB protocols simultaneously. "You can create a dual-protocol (NFSv3 and SMB, or NFSv4.1 and SMB) volume in Cloud Volumes Service for Google Cloud..."

Source: NetApp Cloud Volumes Service for Google Cloud Documentation, "Create a dual-protocol volume," Introduction.

3. NetApp University Courseware (Conceptual Basis): The NetApp Certified Technology Associate curriculum covers NetApp's cloud portfolio, emphasizing the role of Cloud Volumes Service in providing managed, multi-protocol file services within major public clouds.

Source: NetApp NCTA (NS0-005) Exam Objectives, Domain 4: "Describe NetApp Cloud Data Services." This domain includes understanding the use cases for services like Cloud Volumes Service.