【正确答案】 B

【答案解析】语义理解题。由题干定位至首段。通过分析可知，首句中的news是指第二句中提到的too much exercise is bad for you and that doing less could lengthen your life。第二段提到新书：The Joy of Laziness: How to Slow Down and Live Longer，可见这对于那些疏于锻炼者是个好消息，[B]符合文意，故为答案。既然是waiting for，应该是指人，排除[C]。