"Whom" can serve as the object of a preposition.
True; Ex. With whom did you go to the mall?
"Whom" is an object pronoun.
True; Ex. To whom did you give the book?
"Who" and "whom" are personal pronouns.
False; Who and whom are relative pronouns. Personal pronouns are: I, you, he, she, him, her, it, we, they, us, them.
"Who" is a subject pronoun.
True; Ex. Who is running?
