If the driver in front of you moves their arm alternately up and down with short, quick movements, what is being indicated?
A)That they intend to reduce speed considerably.Correct
B)The intention to immobilize the vehicle, in any case.
C)That they are going to reverse.
The intention to immobilize the vehicle or to brake significantly, even when these actions are imposed by traffic circumstances, must be signaled when possible with the brake lights or with the arm, making up and down movements, with the left arm extended and the palm facing down.