It is not only experts in China who are arguing over whether women should work after marriage or not. Worldwide this question is being discussed as an interestingly large number of married women enter the workplace. Take the United States for example. Since 1960, the percentage of married women in the work force has jumped from 31.9 per cent to 59.4 per cent. American women first moved into the paid labour force during the World War II, when men left their jobs to fight. In the last fifty years, more and more women have worked outside the home. And over these years of developing, Americans have changed their social values as a result. In 1975, women aged 35 and above made up half of all working women. And by 1980, 60 per cent were women at the age of 45 and above. Now in Japan, women's work group is M-shaped with middle-aged women and those aged 20-25 at the two peaks. According to statistics , 37.7 per cent of Japanese women at childbearing age(25-29) still engaged themselves in work in 1980. and the number reached 50 per cent the next year. Being a housewife has always been regarded as a "graceful occupation" in Japan. Some young Japanese women believe it is good to be a " professional housewife". However, old attitudes have been changing everywhere, and sometimes just out of economic necessary. In recent years, a great number of city housewives have poured out of homes to take part time jobs. Even the UN has given its support.. The 34thCongress of the United Nations in 1979 put forward the decision for formal agreement on the getting rid of discrimination  against women. So far, most UN members have agreed on it, but some still haven't,  including the United States. More and more women have taken jobs outside for the reason that   _  .
they have no children to take care of they have no housework to do they want to make more friends they want to improve their living conditions
Question: It is not only experts in China who are arguing over whether women should work after marriage or not. Worldwide this question is being discussed as an interestingly large number of married women enter the workplace. Take the United States for example. Since 1960, the percentage of married women in the work force has jumped from 31.9 per cent to 59.4 per cent. American women first moved into the paid labour force during the World War II, when men left their jobs to fight. In the last fifty years, more and more women have worked outside the home. And over these years of developing, Americans have changed their social values as a result. In 1975, women aged 35 and above made up half of all working women. And by 1980, 60 per cent were women at the age of 45 and above. Now in Japan, women's work group is M-shaped with middle-aged women and those aged 20-25 at the two peaks. According to statistics , 37.7 per cent of Japanese women at childbearing age(25-29) still engaged themselves in work in 1980. and the number reached 50 per cent the next year. Being a housewife has always been regarded as a "graceful occupation" in Japan. Some young Japanese women believe it is good to be a " professional housewife". However, old attitudes have been changing everywhere, and sometimes just out of economic necessary. In recent years, a great number of city housewives have poured out of homes to take part time jobs. Even the UN has given its support.. The 34thCongress of the United Nations in 1979 put forward the decision for formal agreement on the getting rid of discrimination  against women. So far, most UN members have agreed on it, but some still haven't,  including the United States. More and more women have taken jobs outside for the reason that   _  .
A. they have no children to take care of
B. they have no housework to do
C. they want to make more friends
D. they want to improve their living conditions
Answer: