The correct answer is A. 21354.
The word “prior” means “before.” In this sentence, it is used to indicate that something happened before the speaker came to see the person. The word “he” refers to the person who came to see the speaker. The word “came” means “arrived.” The word “to” is a preposition that indicates movement towards a destination. The word “me” is a pronoun that refers to the speaker.
The other options are incorrect because they do not make sense in the context of the sentence. Option B, 23145, is incorrect because the word “prior” cannot come after the word “he.” Option C, 25413, is incorrect because the word “came” cannot come after the word “prior.” Option D, 25314, is incorrect because the word “to” cannot come after the word “came.”