You are presented with the question "What movement causes local changes to the condition of the atmosphere?" and the following answer choices: 
- air mass over the moon
 - air mass under Earth's surface
 - a hemisphere is tilted away from the sun
 - energy of moving objects
 - air mass over Earth's surface
 - pressure differences.
 - wind and erosion
 - core mass under Earth

Now knowing that the movement of an air mass over Earth 's surface causes local weather changes and weather is the condition of the atmosphere, choose the best answer.


 

     air mass over Earth's surface    