Answer the following question given this paragraph: 

A mountain-building event is called an orogeny . Orogenies take place over tens or hundreds of millions of years. Continents smash into each other. Microcontinents and island arcs smash into continents. All of these events cause mountains to rise.


Q: What is the term for a mountain-building event?

 Choices:

- glaciation

- volcanism

- erosion

- orogeny

A:
orogeny
