Northern Trail Outfitters uses a custom object to track travel requests.

Feed Tracking is the correct feature because Salesforce can automatically generate feed updates when a tracked field changes on a record. Salesforce Help explains that feed tracking detects changes to tracked record fields and posts updates to the feed. It can also be configured for custom objects.

For this scenario, the app builder would track the travel request approval/status field. When the request becomes Approved, Salesforce posts that tracked change automatically on the record feed.

Why others are incorrect:

Auto-response rule sends automatic email responses, mainly for Lead/Case scenarios.

Approval process manages record approval routing, but the feature that creates automatic feed posts for field changes is Feed Tracking.

Feed quick action is manual, not automatic.

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