A. laugh much more than they do in everyday B. laugh much louder than they do in everyday C. receive special training in how to laugh D. learn to laugh while doing other exercises 参考答案:A 答案解析:[定位] 根据题干body exercise定位到原文最后一句。[解析] body workout。从第四段第九句可以推知,每天上百次的笑才能达到一定的活动量,而第二段指出成年人平均每天才笑17次,A