Answer: C. helps readers understand how rough the water was
Explanation:
Similes are a type of figure of speech that enable one to compare something to another thing so that a better depiction of the scenario is painted. It usually uses the words 'like' and 'as'.
In writing that the waves tossed the people around like rag dolls, the author wanted the reader to know how rough the waves were such that the water was able to move people around like they were as light and easy to carry as rag dolls.
As a general rule, when using a library database or a search engine, you'll find more relevant results if your search terms A. use only partial names or titles.