The correct answer is B. Exposition
Step-by-step explanation:
In writing, the word exposition refers to a type of text that mainly explains, describes, clarifies or provides information about a specific subject or situation. Because of this, this type of writing is commonly written in prose, follows language rules and conventions and is used with the purpose of making the reader aware of something. Additionally to this, exposition texts are usually written based on facts and follow a specific organization to make the explanation in it as clearly as possible. Considering this, it can be concluded, clear, explanatory prose is called exposition because this is the type of text that is written in prose and whose main purpose is to explain and clarify.