Question

What is an example of mechanical weathering?

-the secretion of acids by tree roots
-the exposure of limestone to acid rain
-the formation of rust on iron
-the freezing and thawing of water in rock

Answer 1

C. The formation of rust on iron.

Step-by-step explanation:

"Mechanical" implies machinery. Iron is the only thing of the options that has to do with machinery. So C should be the right answer.