单选题
Harry: I didn't know you play billiards. Are you having fun?John: I'm having a great time. ______ What are you doing?
【正确答案】
B
【答案解析】[注释] I'm having a great time．用来回应前面的问题。后面的表达法应为反问对方， B项选择的How about you?引导后面的问句What are you doing?这两个句子互相关联。其他选择项的表达法与此处的语境不符。