How should pilots respond to a "change in frequency" command?

• A. By repeating their current altitude
• B. By switching to the designated frequency and acknowledging
• C. By confirming their navigation route
• D. By adjusting their speed accordingly

Answer: (B)

When a pilot receives a "change in frequency" command from air traffic control, they should switch to the designated frequency and acknowledge the instruction. This response confirms that the pilot has understood the command and will transition to the new frequency for communication. By acknowledging, the pilot also keeps the controller informed that they are following the instruction, which is crucial for maintaining effective communication and coordination during flight operations.

The other options do not directly address the requirement of changing frequencies. Repeating current altitude provides irrelevant information in this context, confirming a navigation route does not facilitate the frequency change, and adjusting speed is not a necessary action related to changing frequencies. Thus, the chosen response ensures that communication between the pilot and air traffic control remains clear and efficient.