Your organization is using Google Workspace, Google Cloud, and a third-party SIEM.

The standard and most efficient way to stream logs from Google Cloud (including Workspace logs that are shared with Google Cloud) to an external SIEM is via Cloud Logging Sinks pointing to Pub/Sub.5

According to Google Cloud Documentation (Architecture for exporting Cloud Logging logs):

"To stream logs to a third-party SIEM in real-time, you should create a log sink in Cloud Logging. The sink filters for specific logs (e.g., resource.type="audited_resource" and methodName:"login") and exports them to a Pub/Sub topic. The SIEM can then subscribe to this topic to pull events immediately as they are generated."

Why other options are incorrect:

A is incorrect: Exporting to Cloud Storage is for long-term archiving/compliance and is not real-time (it usually involves batched files every few hours).

C is incorrect: Polling via CLI is not scalable, introduces latency, and is prone to failure in production environments.

D is incorrect: Google Workspace does not have a native "direct push" feature for SIEM endpoints; it typically requires an intermediate step like Pub/Sub or BigQuery.