The process in which rocks are formed, change, and break down is called
rock transition
volcanic activity
the earth cycle
the rock cycle

The Rock Cycle is the process in which rocks are formed, changed, and broken down. An igneous rock can either change into a sedimentary or into a metamorphic rock; just the same that a sedimentary rock can change into an igneous rock or metamorphic rock. Factors like heat, water, and air can break and form new types of rocks in a continuous cycle. 

The rock cycle never stops; it is a continuous process that occurs through time. A mountain that is composed of metamorphic rocks can easily be washed away by streams and new sedimentary rocks can be formed through this process.