A vehicle driver extends their arm horizontally with the palm of the hand facing backward, what does this indicate?
A)That they are going to turn left.
B)That they intend to immobilize the vehicle or considerably slow down.
C)That they are going to reverse.Correct
# Explanation
When a driver extends their arm horizontally with the palm of the hand facing backward, they are making a **manual signal for reversing**. This signal warns other road users that the vehicle is going to move backward. It is a clear and visible communication that replaces or complements the vehicle's reverse lights.