Fact 1: The movement of an air mass over Earth 's surface causes local weather changes.

Fact 2: Air mass movements are also influenced by mountain barriers.

Given the two facts above, answer the question "what can mountain barriers influence?" with the following options: 
- erosion
 - social media
 - population movement
 - watershed
 - local weather
 - gravity
 - Animal survival
 - Mount Everest


 

     local weather    