The correct answer is D. Record-triggered flow.

The requirement is automatic: when an Account Type changes to Past-Customer, all directly related Contacts must have their Status updated to Re-Market. A record-triggered flow is the correct declarative automation because it can run when an Account record is updated and then update related Contact records. Salesforce describes record-triggered flows as automation that runs automatically when records are created, updated, or deleted. Salesforce also documents that Flow can update records related to the record that triggered the flow.

Validation rules only prevent invalid saves. Lightning components are UI elements. Screen flows require user interaction, while this requirement needs background automation.

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