Task: Question Answering
Input (English): Question: A metal company's old machine makes bolts at a constant rate of 100 bolts per hour. The company's new machine makes bolts at a constant rate of 150 bolts per hour. If both machines start at the same time and continue making bolts simultaneously, how many minutes will it take the two machines to make a total of 400 bolts?

 Option A:  36

 Option B:  72

 Option C:  96

 Option D:  144

 Option E:  180
Output (English): Option C