The correct answer is B. Hongwu felt that a strong military was necessary to prevent a rebellion by the Mongols. The Mongols were China's neighbor to the north and now be would be called modern-day Mongolia and Manchuria (northern China). Even though they had been driven away, Hongwu knew they still posed a threat. He consolidated a huge army and the army was also taught how to grow crops in case their military positions became sedentary. However, in the end they were still defeated.