If you observe that the white vehicle has just started moving into the left lane, can you begin the overtaking manoeuvre?

A)No, only if it signalled beforehand.
B)Yes, you must carry out the manoeuvre as soon as possible so as not to hinder the other vehicle.
C)No, because it has priority.Correct
If the vehicle following us has started moving into the left lane, it has priority to overtake, so we must not begin the overtaking manoeuvre until it has completed its manoeuvre.
If we intend to overtake a vehicle and it signals its intention to move to the same side, it has priority. However, if after a reasonable period of time it does not begin to move, we may overtake it, having first warned it with acoustic or optical signals.
If we intend to overtake a vehicle and it signals its intention to move to the same side, it has priority. However, if after a reasonable period of time it does not begin to move, we may overtake it, having first warned it with acoustic or optical signals.