Which of the following sentences shows a demonstrative pronoun?

A demonstrative pronoun is a word that points to specific things or people in a way that indicates their relative location (near or far) in relation to the speaker. In this case, the word "this" in the sentence "This is mine" serves as the demonstrative pronoun. It specifically identifies a singular object that is close to the speaker, clearly indicating ownership.

While the other sentences contain demonstrative pronouns such as "these" and "those," they function as demonstrative adjectives because they describe nouns (books and cats) rather than standing alone as pronouns. "This," on the other hand, functions independently in the sentence, clearly designating a particular item that belongs to the speaker. This distinction is critical in understanding the grammatical roles of words in different contexts.