Fact 1: The surface of a beach is formed by mechanical weathering.

Fact 2: Sandy and dusty surfaces get hotter during the day, like beach sand.

Given the two facts above, answer the question "What is a beach formed by?" with the following options: 
- movement of tectonic plates
 - heat change
 - mechanical weathering
 - By coral exoskeletons
 - seasonal changes
 - patch reefs
 - sedimentation
 - Nurseries of the ocean.


 

   mechanical weathering      