Question

Which personal pronoun agrees with the antecedent in this sentence? Someone accidentally left __________ backpack on that park bench. A. its B. his or her C. their

Answer 1

Someone accidentally left B. His or her back back on that park bench. You are referring to a person.

Answer 2

Someone accidentally left their backpack there.
It is their because thier is referring to the known gender and it is a wordly term to define that.
Hope this helps!