Answer:
The sentence that has two antecedents and one pronoun is C. Abe and Peter gave their dog a bath.
Explanation:
The sentence Abe and Peter gave their dog a bath contains two antecedents -Abe and Peter- and a pronoun -their- that refers to those antecedents. As the pronoun must agree in number with its antecedent, and this sentence has two antecedents, the pronoun is plural -their.