The person . . . . . . . talks too much is seldom respected. A. whom B. who C. whose D. None of above

The correct answer is: B. who

The sentence is in the simple present tense, and the subject is “person.” The verb “talks” is in the third person singular, so the pronoun “who” is used to refer to the person.

The pronoun “whom” is used to refer to the object of a verb or preposition. In this sentence, the person is the subject of the verb “talks,” so “whom” is not the correct pronoun.

The pronoun “whose” is used to show possession. In this sentence, there is no possession, so “whose” is not the correct pronoun.

The answer is B. who.