Why do people feel so rushed? Part of this is a perception   problem. Generally, people in rich countries have more free time than they used to. This is particularly true in Europe, but even in America free time has been inching up. Women's paid work has risen a lot over this period,but their time in unpaid work,like cooking and cleaning, has fallen even more significantly, thanks in part to dishwashers, washing machines and microwaves, and also to the fact that men shift themselves a little more around the house than they used to. The problem, then, is less how much time people have than how they see it. Ever since a clock was first used at a workplace to record labor hours in the 18th century, time has been understood in relation to money. Once hours are financially quantified  , people worry more about wasting, but tend to save or use them more profitably. When economies grow and incomes rise, everyone's time becomes more valuable. And the more valuable something becomes, the rarer it seems. Once seeing their time in terms of money, people often _ the former to maximize the latter. Workers who are paid by the hour volunteer less of their time and tend to feel more upset when they are not working. The relationship between time, money and anxiety is something Gary Becker noticed in America's post-war boom years. "If anything, time is used more carefully today than a century ago," he noted in 1965. He found that when people are paid more to work, they tend to work longer hours, because working becomes a more profitable use of time. So the rising value of work time puts pressure on all time. Leisure time starts to seem more stressful, as people are forced to use it wisely or not at all. Women's time in unpaid work has fallen partly because   _  .
men's ability to support a family has been improved men's involvement in housework has increased women's leisure time was taken up by heavy housework women become more skilled at household equipment
Question: Why do people feel so rushed? Part of this is a perception   problem. Generally, people in rich countries have more free time than they used to. This is particularly true in Europe, but even in America free time has been inching up. Women's paid work has risen a lot over this period,but their time in unpaid work,like cooking and cleaning, has fallen even more significantly, thanks in part to dishwashers, washing machines and microwaves, and also to the fact that men shift themselves a little more around the house than they used to. The problem, then, is less how much time people have than how they see it. Ever since a clock was first used at a workplace to record labor hours in the 18th century, time has been understood in relation to money. Once hours are financially quantified  , people worry more about wasting, but tend to save or use them more profitably. When economies grow and incomes rise, everyone's time becomes more valuable. And the more valuable something becomes, the rarer it seems. Once seeing their time in terms of money, people often _ the former to maximize the latter. Workers who are paid by the hour volunteer less of their time and tend to feel more upset when they are not working. The relationship between time, money and anxiety is something Gary Becker noticed in America's post-war boom years. "If anything, time is used more carefully today than a century ago," he noted in 1965. He found that when people are paid more to work, they tend to work longer hours, because working becomes a more profitable use of time. So the rising value of work time puts pressure on all time. Leisure time starts to seem more stressful, as people are forced to use it wisely or not at all. Women's time in unpaid work has fallen partly because   _  .
A. men's ability to support a family has been improved
B. men's involvement in housework has increased
C. women's leisure time was taken up by heavy housework
D. women become more skilled at household equipment
Answer: