Which statement best describes the purpose of an IFF transponder's challenge-response mechanism?

Which statement best describes the purpose of an IFF transponder's challenge-response mechanism?

• A. It enables two-way data link communications.
• B. It responds to interrogation with a code; challenge-response ensures expected transponder logic and reduces friendly-fire risk.
• C. It is used for altitude reporting.
• D. It encrypts voice communications.

Answer: (B)