How did oasis towns benefit the silk road

The Silk Road often traversed over long stretches of barren land which left caravans open to marauders and thieves. As towns began to grow up around the oasis, the traders on the Silk Road would feel safer just traveling between towns instead of long stretches where no one lived. The military would take great effort to keep the roads between the town in good condition enabling them to move troops easily but the good roads aided the traveling merchants also.

The answer is c because i know the answer is c