The pronoun that has an unclear antecedent in the above is the pronoun C. Them.
Why does "Them" have an unclear antecedent?
When a pronoun has an unclear antecedent, it means that there is a confusion as to which noun the pronoun is being used to refer to.
In the above, the pronoun, "them" could be referring either to the sixth-grade students or to the elderly people. It is unclear which noun is being referred to.
In conclusion, option C is correct.
Find out more on unclear antecedents at https://brainly.com/question/1203147.
