题目

．设a，b∈(0，＋∞)，则a＋，b＋( ) A．都不大于2                             B．都不小于2        C．至少有一个不小于2                     D．至少有一个不大于2 答案：CIf you want to be thinner and healthier, you'd better eat _____food and take _____exercise. [     ]A. more; fewer    B. more; less     C. fewer; more     D. less; more