单选题
下面有3篇短文,每篇短文后有5道题。请根据短文内容,为每题确定1个最佳选项。
{{B}}第一篇{{/B}}
Walking to Exercise the Brain

Do you think sitting and studying all the time will improve students'grades? Think again.Getting some exercise may help,too.
New research with older people suggests that taking regular walks helps them pay attention better than if they didn't exercise.
Previous research had shown that mice learn,remember,and pay attention better after a few weeks of working out on a running wheel.Mice that exercise have greater blood flow to the brain than those who don't.Their brain cells also make more connections.
Neuroscientists(神经科学家)from the University of Illinois at Urbana-Champaign wanted to find out if the same thing is true for people.First,they measured the physical fitness of 41 adults,ages 58 to 77,after each person walked 1 mile.Then,participants looked at arrows on a computer screen and had to use computer keys to show which way one particular arrow was pointing.
Adults who were physically fit were faster at the arrow task,and their answers were just as accurate as their less-fit peers,the researchers found.The fitter participants also had more blood flow to a part of their brain responsible for paying attention and making decisions.
In a second study,15 elderly people who completed a 6-month aerobic-training(有氧运动)course were faster at attention tasks compared with 14 seniors who just did stretching and toning(韵律操)exercises for the same amount of time.
So,even going for a walk every 2 or 3 days for just 10 to 45 minutes can help.That should be good news for the elderly.
The effects of exercising on the brains of younger people haven't been studied yet.Still,it can't hurt to take occasional breaks and go for a walk or run around with friends.Whatever you do,though,don't try to read and walk at the same time.You could end up hurting yourself!
单选题 Walking regularly helps elderly people
【正确答案】 C
【答案解析】[解析] 文中第二段提到“对老年人的新研究表明,相对于不锻炼,经常散步有助于帮助他们更好地集中精力”,故选C。
单选题 After taking exercise for a few weeks,the mice were found to have
【正确答案】 C
【答案解析】[解析] 短文第三段第二句提到“运动的老鼠大脑中的血液流量大于不运动的”,故选C。
单选题 The first study on 41 elderly people found
【正确答案】 B
【答案解析】[解析] 第五段第一句提到,“研究者发现身体健康的成年人完成箭头测试的速度更快,他们的答案和身体状况不佳的人一样准确。”故选B。
单选题 It can be good for health when one takes a walk every 2 or 3 days for at least
【正确答案】 D
【答案解析】[解析] 短文第七段第一句提到“因此,每两三天仅出去散步10到45分钟也会对健康有益。”而题干问的是“至少”,所以应该是“10分钟”,故选D。
单选题 It is suggested in the last paragraph that people should
【正确答案】 B
【答案解析】[解析] 短文最后一段第三句提到,“但是,不论你做什么,都不要一边走路一边看书”,故选B。