What is the correct response to the question: "Where is she?"?

The selection of "In the library" as the correct response is appropriate because it directly answers the question "Where is she?" with a clear and complete prepositional phrase that specifies the location of the subject (she). This response communicates the necessary information in a straightforward manner, providing clarity and context.

The other responses do not effectively answer the question. "Library be there" is awkward and does not follow standard grammatical structure. "She where" is not a coherent phrase and fails to convey meaning. "There she is" answers more in the context of identifying her presence rather than indicating her location, which does not align with what the question is asking. The clear and direct nature of "In the library" makes it the most suitable choice.