You are presented with the question "What is when rocks are broken down?" and the following answer choices: 
- roof weathering
 - Plant growth is reduced
 - brick weathering
 - Physical weathering
 - remains of prehistoric life
 - at or near the margins
 - home weathering
 - major threat to health

Now knowing that mechanical weathering is when rocks are broken down by mechanical means and pysical weathering is the mechanical breakdown of rocks, choose the best answer.


 

    Physical weathering     