The correct answer is C. A record-triggered flow can run automatically when an Opportunity is updated to Closed Won, create a renewal Opportunity, and notify the contracts team. Salesforce Trailhead explains that record-triggered flows are built around trigger, criteria, and action; for example, when an Opportunity is created or updated and meets criteria, the flow can create another record.

Salesforce Flow can also create records and send emails, which fits both requirements: create the renewal Opportunity and notify an external contracts team.

Why others are incorrect:

A Approval Process is for review/approval routing.

B Outbound Message may notify an external system, but it does not handle the full renewal Opportunity creation requirement by itself.

D Validation Rule only prevents bad data; it does not create records or send notifications.

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