Sentence1: Marge begged her husband Bill for a backyard pool. Sentence2: He finally relented, and the pool was installed. Sentence3: Soon, Marge was throwing weekly pool parties. Sentence4: At one party, she saw a curvy neighbor in a bikini talking to Bill. 
 (A) Marge put a new key on her keychain. (B) Marge felt a pang of regret about putting in the pool right then.
A