The marketing director is concerned that too many car parts were given away for free...

The correct answer is C. Approval process.

The key requirement is that the manager’s sign-off on free parts must be processed. Salesforce approval processes are designed to automate record approval, define approval steps, assign approvers, and perform actions when records are approved or rejected. Salesforce Trailhead gives a similar discount-management example where discount percentage is tracked and manager approval is requested through an approval process.

Why others are incorrect:

A. High Velocity Sales is for sales engagement/cadences, not approval sign-off.

B. Quotes may help with pricing, but it does not by itself process manager approval.

D. Checkbox can store a value but cannot route approval.

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