I'm not sure, but I think it would be mud.
The natural cause of acid rain is the <span>chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air.</span>
Creep is a solid material's tendency to deform permanently under pressure or stress.
So, a cracked telephone pole or a broken sidewalk would be examples.
All of the answers would be correct,
hope this helped!! <span />
