Dad agreed to the afternoon lesson because that was the time when ______. A. he was at home so that he could know how Susie was doing B. he had fewer clients so that Susie's piano lesson would bother them the least C. he was free and could enjoy listening to Susie playing the piano D. he was good-tempered and could endure Susie's practicing D. he was good-tempered and could endure Susie's practicing