Answer: The correct answer is B) A car that rounds a curve at a constant speed.
Explanation-
Acceleration is defined as a rate of change of velocity. Hence, it is a vector quantity that is it has magnitude as well as direction.
When a car moves along a curve with constant speed, its magnitude of speed remains constant but its direction of motion keeps on changing. The change in its direction leads to an acceleration.
Thus, option B) represents that the car is accelerating.