Since the data volume is stable and updated frequently in an external system, and there's no need to store it in Salesforce, Salesforce Connect is the best choice. It allows real-time access to external data using External Objects. This can be used alongside Flows for automation.

C. Correct — Salesforce Connect provides real-time access, and Flows can automate interaction with that data.

Incorrect Options:

A. ETL tools are for batch data movement, not real-time access.

B. External Services is more suitable for actions (not data listing or queries).

D. Local Actions are used in Screen Flows, not ideal for real-time data integration.

Reference Extracts from Salesforce Process Automation Study Guide:

“Salesforce Connect allows integration with external data sources using External Objects for real-time data access.”

“Use Flow to automate interactions with external objects when data doesn’t need to be stored.”

=========================================================