Final answer:
Decreasing the time it takes for a car to cover the same distance increases the car's speed, according to the basic formula speed = distance / time.option A.
Step-by-step explanation:
When we decrease the time it takes for a car to travel over the same distance, the effect would be an increase in the speed of the car. Speed is defined as the distance travelled per unit of time. Therefore, if the distance remains constant and the time decreases, the speed must increase accordingly. This is represented by the basic formula for speed: speed = distance / time. Hence, the correct answer to the question is: 'a-increase the speed'.
When the time it takes for a car to travel over the same distance is decreased, it will increase the speed. This is because speed is defined as the distance traveled divided by the time taken, so if the time is decreased while the distance remains the same, the speed will increase.