单项选择题

【案例分析题】
Why Do People Shrink？
Did you ever see the movie Honey，I shrunk the kids？It’s about a wacky（古怪的）dad （who’s also a scientist）who accidentally（偶然的）shrink’s his kids with his homemade miniaturizing （使小型化）invention.Oops!The kids spend the rest of the movie as tiny people who are barely visible while trying to get back to their normal size.
（46）It takes place over years and may add up to only one inch or so off of their adult height （maybe a little more，maybe less），and this kind of shrinking can*t be magically reversed，although there are things that can be done to stop it or slow it down.But why does shrinking happen at all？
（47）As people get older，they generally lose some muscle and fat from their bodies as part of the natural aging process.Gravity （the force that keeps your feet on the ground）take hold，and the bones in the spine，called vertebrae（椎骨），may break down or degenerate，and start to collapse into one another.（48）.But perhaps the most common reason why some older people shrink is because of osteoporosis （骨质疏松症）.
Osteoporosis occurs when too much spongy（海绵）bone tissue （which is found inside of most bones）is broken down and not enough new bone material is made.（49）.Bones become smaller and weaker and can easily break if someone with osteoporosis is injured.Older people—especially women，who generally have smaller and lighter bones to begin with—are more likely to develop osteoporosis.As years go by，a person with osteoporosis shrinks a little bit.
Did you know that every day you do a shrinking act？You aren’t as tall at the end of the day as you are at the beginning.（50）.Don’t worry，though.Once you get a good night’s rest，your body recovers，and the next morning，you’re standing tall again.
(46)（）

A. They end up pressing closer together, which makes a person lose a little height and become shorter.
B. That's because as the day goes on, water in the disks of the spine gets compressed (squeezed) due to gravity, making you just a tiny bit shorter.
C. Over time, bone is said to be lost because it's not being replaced.
D. Luckily, there are things that people can do to prevent shrinking.
E. For older people, shrinking isn't that dramatic or sudden at all.
F. There are a few reasons.

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多项选择题

根据消费目的，消费者的消费类型可分为（）。

A．物质功能型消费
B．精神情感型消费
C．身份炫耀型消费
D．减少失调型消费
E．自我实现型消费

单项选择题

【案例分析题】
A meager（不足的）diet may give you health and long life，but it’s not much fun—and it might not even be necessary.We may be able to hang on to most of that youthful vigor even if we don’t start to diet until old age.
Stephen Spindler and his colleagues from the University of California at Riverside have found that some of an elderly mouse’s liver genes can be made to behave as they did when the mouse was young simply by limiting its food for four weeks.The genetic rejuvenation（恢复活力）won’t reverse other damage caused by time for the mouse，but could help its liver metabolize（新陈代谢）drugs or get rid of toxins（毒素）.
Spindler’s team fed three mice a normal diet for their whole lives，and fed another three on half-rations.Three more mice were switched from the normal diet to half-feed for a month when they were 34months old—equivalent to about 70human years.
The researchers checked the activity of 11，000genes from the mouse livers，and found that 46changed with age in the normally fed mice.The changes were associated with things like inflammation and free radical production（自由基）—probably bad news for mouse health.In the mice that had dieted all their lives，27of those 46genes continued to behave like young genes.But the most surprising finding was that the mice that only started dieting in old age also benefited from 70per cent of these gene changes.
’This is the first indication that thee effects kick in pretty quickly，’says Huber Warner from the National Institute on Aging near Washington，D.C.
No one yet knows if calorie works in people as it does in mice，bus Spindler is hopeful.’There’s attracting and tempting evidence out there that it will work，’he says.
If it does work in people，there might be good reasons for rejuvenating the liver.As we get older，our bodies are less efficient at metabolizing drugs，for example.A brief period of time of dieting，says Spindler，could be enough to make sure a drug is effective.
But Spindler isn’t sure the trade-off（交换）is worth it.’The mice get less disease，they live longer but they’re hungry，’he says.’Even seeing what a diet does，it’s still hard to go to a restaurant and say：’I can only eat half of that’.’
Spindler hopes we soon won’t need to diet at all.His company，Life Span Genetics in California，is looking for drugs that have the effects of calorie restriction.
According to the passage, which of the following is true?（）

A. Eating less than usual might make us live longer.
B. We don't need to go on a diet.
C. A meager diet may be fun.
D. We have to begin dieting from childhood.