The correct answer is the following: <u><em>option B. Mountain ranges were formed when continents collided.</em></u> A mountain range or a hill range is a series of mountains and/or hills arranged in a line and connected by high round. Mountain ranges are a result, in most cases, of a geological process called a plate tectonics, which is the motion of large plates, like continents. This theory that supports the concept of continents colliding, explains why there are mountain ranges.