The correct answer is D. Evan went to the gym with the boys from work.
Explanation
The sentence "He went to the gym with them" is a very ambiguous sentence that does not specify who is meant by the pronouns "he" and "them". So the best option to correct this confusing pronoun antecedent would be to give specificity to these pronouns by giving them proper names or specific characteristics. So the correct answer is D. Evan went to the gym with the boys from work.
