A participle is a verb that functions as an adjective which modifies the given noun or pronoun. From the given sentence above, the participle is the word "loosened". This word is used to describe the noun rocks. Thus, the answer is letter A.
You write a abcdefghijklmnopqrstuvwxyz
A would make more sense as the answer because a persuasive essay is opinionated so you should have opiniobs that go along with yours to be able to have more of a "backup" if you will. More people saying helps the reader feel more obligated to that opinion
The right choice would be D. Premier : Country :: Teacher : school.
Other options doesn't match at all. They are off point, especially A and B.
A) Convert
Scouts try to recruit you for the army the some way a missionary would try to convert you to their religion.