What is a “U-turn”?

1. Any turn not in a right angle is called a U-turn.
2. Correct answer: A turn in which the driver turns back to the direction he came from (turns and drives to the opposite direction)
3. Only a turn in which the driver drives in a roundabout and returns to the direction he came from.
4. A turn in which the driver makes a 360 degrees round.

WhyA U-turn is a maneuver after which you drive back the way you came. It is 180 degrees, not 360, and not necessarily at a roundabout.