Which signal indicates parking brakes should be applied?

• A. Crossing arms extended above his head
• B. Arms down, palms facing inwards, moving arms from extended position inwards
• C. Horizontally moving his hands, fingers extended, palms toward ground
• D. Raise arm and hand, with fingers extended, horizontally in front of body, then clench fist

Answer: (D)

The signal for parking brakes being applied uses a clearly visible, two-step gesture: raise the arm and hand with the fingers extended, held horizontally in front of the body, then finish by clenched fist. This combination communicates a definite action and its completion in a way that’s easy to see from a distance and under different lighting, reducing the chance of misinterpretation on the ground. The raised, extended hand grabs attention, and the final clenched fist signals that the brakes are now set. The other gestures don’t match this standard parking-brake signal and could be misread as other commands, so they aren’t used to indicate braking.