A、Exercise every day. B、Take diet pills. C、Go on a diet. D、Sleep more. D主旨大意题。题意是：“对那些想减肥的人们，Patel的建议是……”很明显，这道题在考察整段文字要表达什么。文中细

Here’s a dreamy weight-loss plan: take a nap. That’s the message from work by Sanjay Patel at Case Western Reserve University in Cleveland, Ohio. His study of more than 68,000 women has found that those who sleep less than 5 hours a night gain more weight over time than those who sleep 7 hours a night.
    Controlling for other differences between the groups, Patel found that women who slept 5 hours or less gained 0.7 kilograms more on average over 10 years than 7-hour sleepers. The short-sleeping group was also 32 percent more likely to have gained 15 kilograms or more, and 15 percent more likely to have become obese.
    Significantly, the short-sleepers consumed fewer calories than those who slept 7 hours, says Patel, who presented his results this week at the American Thoracic Society International Conference in San Diego, California. This finding overturns the common view that overeating among the sleep-deprived explains such weight differences.
    Lower metabolic rate resulting from less sleep may be the reason behind the weight gain, Patel suggests. "It obviously also suggests that getting people to sleep more might be a relatively easy way to help people lose weight," he says.
21. What did Patel’s study indicate?
22. How many subjects did Patel have in his study?
23. According to Patel’s study, which of the following is not true?
24. According to Patel, what might be the reason behind the weight differences?
25. What suggestion will Patel give to those who want to lose weight?