75
50
90
100
Answer is Right!
Answer is Wrong!
The correct answer is D. 100%.
According to the Federal Railroad Administration (FRA), passenger trains must have 100% of brake power in order to be enroute. This means that the train must have enough braking power to stop safely in the event of an emergency.
Option A, 75%, is incorrect because it is not enough brake power to stop a train safely in an emergency. Option B, 50%, is also incorrect for the same reason. Option C, 90%, is incorrect because it is not the minimum amount of brake power required by the FRA.
Therefore, the correct answer is D. 100%.