What is the stopping distance for 30mph?

Answer: C — 75 ft

Stopping distance is the total distance covered by a vehicle from the moment the brakes are applied to the moment the vehicle comes to a complete stop. Option A is incorrect because it is too short for the stopping distance at 30mph. Option B is also incorrect because it is still too short for the stopping distance at 30mph. Option D is incorrect because it is too long for the stopping distance at 30mph. Therefore, the correct answer is C, as it is the most accurate approximation of the average stopping distance of 30mph, which is around 75 feet.