Answer:
D) The object is accelerating in the negative direction.
Step-by-step explanation:
When a body is moving in positive direction (positive velocity) and slows down then it is said to have a negative acceleration because the acceleration is in the opposite direction to that of velocity(motion of the car). So, option D must be true. The negative acceleration can either be constant or changing, depending on how the velocity is changing. So, option B) Its negative acceleration is constant, is possible but not a must.
Therefore, the correct answer is given by the D option.