Yes, both "she" and "they" are correct answers. "She" refers to Stacy, who is going to the gym. "They" refers to both Stacy and Response Area, who are going to the gym together.
wait but i thought the first sentence is 2 people
Apologies for the confusion. If the first sentence is referring to two people (Stacy and Response Area), then the correct pronoun to use would be "they." So, the correct answer would be "they."
But then it would sound like Stacy and they are going to the gym
Apologies for any confusion. In that case, if the first sentence is referring to Stacy and Response Area as separate individuals, the correct pronouns would be "she" for Stacy and "they" for Response Area.
