Answer: `roles/spanner.viewer`

## Explanation **Correct Answer: B) `roles/spanner.viewer`** Let's analyze each option: **A) `roles/spanner.databaseUser`** - This role provides read/write access to Cloud Spanner databases, which includes data access. This is too permissive for support engineers who only need monitoring access. **B) `roles/spanner.viewer`** - This role provides read-only access to Cloud Spanner resources, allowing users to view configuration, metadata, and monitoring information without accessing the actual data. This is the appropriate role for support engineers who need monitoring access but no data access. **C) `roles/owner`** - This is the Owner role at the project level, which provides full control over all resources in the project, including data access. This is far too permissive. **D) `roles/viewer`** - This is the basic Viewer role at the project level, which provides read-only access to all resources in the project. While this includes monitoring access, it also potentially allows viewing of other resources beyond Cloud Spanner, which may not be necessary. **Key Points:** - `roles/spanner.viewer` is specifically designed for Cloud Spanner monitoring scenarios - It allows viewing of Cloud Spanner instances, databases, and their configurations - It provides access to monitoring metrics and logs - It does NOT grant access to read or write data in the databases - This follows the principle of least privilege by granting only the specific permissions needed For support engineers who need to monitor Cloud Spanner performance, view metrics, and troubleshoot issues without accessing sensitive data, `roles/spanner.viewer` is the most appropriate choice.

Author: Rodrigo Sales