Fact 1: The color of leaves on deciduous trees usually changes in the autumn season.

Fact 2: Fall colors begin as deciduous trees lose their leaves.

Given the two facts above, answer the question "Fall begins as deciduous trees lose their leaves when?" with the following options: 
- It becomes dormant
 - Plant growth is reduced
 - in the autumn season
 - deforestation
 - Physical weathering
 - in the winter season
 - in the spring season
 - in the freezing season


 

   in the autumn season      