They found that at nearly every age, identical twins survived longer than fraterna twins(异卵双生), who in turn, had greater longevity than the general population. The question is why do twins live longer?We already know that a similar longevity effect has been found for marriage. Married people tend to be healthier than unmarried people and thus, live longer. However, drawing clear conclusions from marriage data is complicated because it is unclear whether marriage itself makes people healthie or whether healthie people choose to get and stay married longer. Since twins have no choice about their twindness, it is easier to tease out (梳理) the contributing factors to their longevity. The researchers concluded twins' greater longevity results from three factors:First, twins are more likely to provide emotional and other kinds of support during difficult and stressful times. Since identical twins are more similar than fraterna twins, they might be better at knowing when their twin needs support and how to provide it—thus explaining the small advantage in longevity identical twins have over fraterna twins.Second, the lifelong close relationship twins have might buffer (缓冲) them from risky behaviors as they have someone looking out for their best interests. The researchers concluded this was especially true of male twins, as men are more prone to risky behaviors than women.Last, the mutual care twins of A habit can not only prevent risky2/s47.What can we infer from the second paragraph?A It is marriage that makes people healthie and live longer.B The relationship between marriage and health is quite unclear.C Healthier people choose to get married and maintain it.

A new study analyzed data from one of the oldest and most complete regisreries of information about twins in the world—2,932 pairs of same-same twins born in Denmark between 1870-1900—and compared their lifespans to that of the general population. They found that at nearly every age, identical twins survived longer than fraterna twins(异卵双生), who in turn, had greater longevity than the general population. The question is why do twins live longer?We already know that a similar longevity effect has been found for marriage. Married people tend to be healthier than unmarried people and thus, live longer. However, drawing clear conclusions from marriage data is complicated because it is unclear whether marriage itself makes people healthie or whether healthie people choose to get and stay married longer. Since twins have no choice about their twindness, it is easier to tease out (梳理) the contributing factors to their longevity. The researchers concluded twins' greater longevity results from three factors:First, twins are more likely to provide emotional and other kinds of support during difficult and stressful times. Since identical twins are more similar than fraterna twins, they might be better at knowing when their twin needs support and how to provide it—thus explaining the small advantage in longevity identical twins have over fraterna twins.Second, the lifelong close relationship twins have might buffer (缓冲) them from risky behaviors as they have someone looking out for their best interests. The researchers concluded this was especially true of male twins, as men are more prone to risky behaviors than women.Last, the mutual care twins of  A    habit can not only prevent risky2/s47.What can we infer from the second paragraph?A It is marriage that makes people healthie and live longer.B The relationship between marriage and health is quite unclear.C Healthier people choose to get married and maintain it.