What is a U-turn?

A U-turn refers specifically to a maneuver in which a driver makes a 180-degree turn to go in the opposite direction. This is correctly characterized as a smooth motion within the road. The essence of a U-turn is to reverse direction without needing to back up or navigate backward, providing a continuous flow of movement.

It typically occurs when there is sufficient space on the road to execute the turn safely and is a common maneuver often performed at locations designated for U-turns or in wide, clear areas of the road. This definition aligns well with option B, highlighting the need for a smooth execution of the turn.

Other choices describe aspects that are not quite right for a U-turn; for instance, a turn made at an intersection usually pertains to a right or left turn and does not necessarily involve reversing direction as a U-turn does. A reverse maneuver to park focuses on backing up rather than making a turn to change directions. Lastly, while using a signal is important for indicating intent to other drivers, not every U-turn must require a prior signal, especially if the movement is smooth and does not impact the flow of traffic significantly. Therefore, B stands out as the option that accurately captures the definition of a U-turn.