A、Married women. B、Married men. C、Unmarried women. D、Unmarried men. D

Welcome to the third lecture in our series on having a baby. New research finds that being a parent could add two years to your life.
   The claim may be met with skepticism by virtually everyone who has experienced the sleep-deprivation and stress of bringing up a child, but the scientists behind the major study are sure that parenthood may well be the secret to a longer life.
   The findings apply to men and women, the researchers claim, although fathers saw their life expectancy increase more than mothers.
   Swedish health experts tracked 1.5 million people and found those who had at least one child had a greater life expectancy. The reason, they suspect, is that children go on to provide vital support to their parents when they get older.
   Writing in the Journal of Epidemiology and Community Health, the researchers said: "Support from adult children to their ageing parents may be of importance for parental health and longevity. "
   At 60 years old, fathers can expect to survive another 20.2 years—two years longer than men with no children, the researchers found. Meanwhile, mothers at 60 can expect to live a further 24.6 years, whereas childless women can expect another 23.1 years—a difference of 18 months.
   The scientists, from the Karolinska Institute in Stockholm, found the older people get, the greater the benefits of having a child.
   At the age of 80, men with children could expect to live a further 7. 7 years, while those without live, on average, seven years. Mothers at the age of 80 could expect a further 9.5 years, while those without would survive an average of only 8.9 years.
   Both married and non-married couples benefited from having children, though unmarried people—and particularly men—seemed to enjoy a stronger result, the research showed.
   This may suggest that unmarried people rely on their children more for support, whereas married couples are also supported by their partner.
Questions 23 to 25 are based on the recording you have just heard.
23. What is parents’ attitude towards the new research?
24. What do we learn about the life expectancy of men and women from the new research?
25. Who will benefit more from having children?