题目

    Why do men die earlier than women? The latest research makes it known that the reason could be that men’s hearts go into rapid decline when they reach middle age.     The largest study of the effects of aging on the heart has found that women’s longevity may be linked to the fact that their hearts do not lose their pumping power with age.     “We have found that the power of the male heart falls by 20--25 percent between 18 and 70 years of age,” said the head of the study, David Goldspink of Liverpool John Moores University in the UK.     “Within the heart th两个角的大小之比是7∶3，他们的差是72°，则这两个角的关系是 [     ]A、相等      B、互余          C、互补            D、无法确定