Mode S is the short form for which term?

• A. Mode Select
• B. Mode S
• C. Selective Mode
• D. Mode Setting

Answer: (A)

This question tests understanding of what Mode S stands for in transponder technology. The S denotes selective, highlighting the ability of the transponder to respond only to interrogations addressed to a specific aircraft. This selective addressing allows unique identification and targeted data exchange, setting Mode S apart from the other modes that broadcast or provide generic replies.

Among the terms given, the one that best captures this idea is the one that emphasizes a mode designed for selective, targeted responses. The others describe broader actions like choosing a mode or changing a setting, which don’t reflect the targeted addressing capability that Mode S provides.