In the PDC model, which type of control is considered the most efficient?

• A. Detective
• B. Preventive
• C. Corrective
• D. Monitoring

Answer: (B)

Preventive controls are the most efficient approach because they stop errors or fraud before they can occur. By putting in place constraints, approvals, validations, and proper separation of duties, you reduce the probability of problems happening in the first place. This means you avoid both the loss from the error and the costs associated with detecting and correcting it later.

Detective controls catch issues after they’ve happened, leading to remediation efforts and potential loss, while corrective controls focus on fixing problems after detection and getting systems back to normal. Monitoring helps ensure controls stay effective, but it doesn’t prevent the issue by itself. So, preventing the issue upfront minimizes risk at a lower overall cost, making preventive controls the most efficient choice.