Multiple choice Directions: Fill in the blank. That is the boy ______ I was speaking of. what who whom None of these Reveal answer Fill a bubble to check yourself C Correct answer Explanation When a relative pronoun follows a preposition ('of'), we must use 'whom' instead of 'who'. 'Whom' is the object case, required after prepositions. Options A (what), B (who), and D don't correctly fill this grammatical position.