The correct answer is B. She's
Explanation:
In grammar, contraction occurs when two words are shortened and combined into one word which is commonly used in speaking and writing to make the language more concise. Additionally, in writing when two words are contracted it is necessary to place an apostrophe (') to represent the missing letters. In the case presented the sentence "It is no surprise that my friend wants to become an entomologist, because _____ so interested in the study of insects" the blank space should be filled with a noun and verb or a pronoun and verb and therefore, the contraction that would be correct in this case is "She's" as this contraction means "she is" and this is the only option in which the apostrophe has been placed correctly as it stands for the "i" omitted.
