阅读下面短文, 根据短文内容, 从短文后各题所给的A、B、C、D四个选项中, 选择最佳选项。

C

    A desert is a difficult place for animals to live, and some have unusual ways of making a living. The Texas lizard has a strange way to keep itself safe. When a predator(掠食动物) gets too close, blood goes out from the lizard's eyes. Then it breathes in much air to make its body look bigger. Another interesting desert animal is the javelina. To make a predator afraid and run away, the javelina bravely faces the animal. It makes a big noise with its teeth. It raises the hard hairs on its back to make itself look bigger. The javelina also gives off a strong smell as a warning when it is afraid. This smell is so strong that javelinas are also called "smelly pigs". Javelinas keep safe by staying close to their family, so there's a good chance they can make a predator change its mind!

    You might think a rain forest would be easier to live in than a desert. After all, there's plenty of food and water in a rain forest. But that also means a lot of animals live there. Being able to climb trees is a useful skill in the rain forest. It allows an animal to keep away from predators. The sloth spends most of its life in the treetops. Its strong, curved claws(爪子) help it climb and hang upside down from branches. The sloth also moves very slowly. It does this so it's not noticed. The aye-aye lives only in the rain forest of Madagascar, near Africa. The aye-aye is a night animal. This helps it to stay safe from daytime predators. However, the number of the aye-aye keeps going down and they may die out. People have hunted it because they think it brings bad luck. Also, much of the rain forest in Madagascar has been cut down, which has destroyed the aye-aye's home. Today there are laws(法律) to keep people from killing it.

You've heard of 3D printing from newspaper and TV programs．It can “print”in plastic，metal，nylon，and over a hundred other materials.3D printing technology has been around since the 1980s，it was not widely used until the early 2010s．The first working 3D printer was created in 1984 by Chuck Hull．

3D printers use many different types of technologies，but they all share one thing in common：they create a three—dimensional(维度的)object by building it layer(层)，by continuing layer, until the whole object is completed．Imagine a baker(面包师)lay down each layer one at a time until the whole cake is formed.3D printing is somewhat similar， but just a bit stricter．How can 3D printers work so well? The most important thing a program，a 3D printer also needs to have instructions for what to print from a computer．It needs a file as well．The file which is a Computer Aided Design (CAD)paper is created with the use of a 3D modeling program．The program creates a paper that is sent to the 3D printer. Along the way，software pieces the design into hundreds，or more likely thousands of layers．The 3D printer builds up one layer at a time，from the bottom to the top，until the object is done．

    3D printings can be used for making many kinds of things such as machine parts， daily life objects，even human organs(器官)using a person's own cells．

Nowadays, Marc．Dillon founds a project which deals with many world famous paintings like Leonardo da Vinci's Mona Lisa, Van Gogh's Sunflower with 3D technology．This project helps the blind people enjoy the fantastic art through touching．In order to provide a good user experience，these 3D paintings have special instruments which can tell people what they touch．

D

    Research proves that nearly half of the cancers diagnosed(诊断) in the UK each year-over 130, 000 in total- are caused by life choices that include smoking, drinking and eating the wrong things.

    Tobacco(烟草) is the biggest factor, causing 23% for cases in men and 15.6% in women, says the Cancer Research UK report. Next comes a lack of fresh fruit and vegetables in men's diets, while for women it is being overweight. Lead author of the report, Professor Max Parkin, said: "Many people believe cancer is related to fate or in the genes(基因), and that it depends on luck whether they get it or not. Looking at all the evidence, it is clear that around 40% of all cancers are caused by things we mostly have the power to change."

    For men, the best advice appears to be: stop smoking, eat more fruit and vegetables and cut down on how much alcohol you drink. For women, again, the best advice is to stop smoking, but also watch your weight.

    In total, 14 lifestyle and environmental factors, such as where you live and the job you do, cause 134, 000 cancers in the UK each year.

    Some risk（风险） factors are well founded, such as smoking's link with lung cancer. But others are less well recognized. For stomach cancer, a fifth of the risk comes from having too much salt in the diet, data suggests. Some cancers, like mouth and throat cancer, are caused almost entirely by lifestyle choices. But others, like gall bladder cancer(胆囊癌), are largely unrelated to lifestyle.

    Public Health Minister, Anne Milton, said: "By making small changes you can cut your risk of serious health problems- giving up smoking, watching you drink, getting more exercise and keeping an eye on your weight."

    Is there intelligent (有智力的) life on other planets? For years, scientists said "no" or "we don't know". But today this is changing. Seth Shostak and Alexandra Barnett are astronomers (天文学家). They believe intelligent life exists (存在) somewhere in the universe. They also think we will soon contact these beings (人；生物).

    Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. "This is long enough for other planets to have intelligent life," say Shostak and Barnett. The second reason is size—the universe is huge. "Tools like the Hubble Telescope (哈勃望远镜) have shown that there are at least 100 billion galaxies," says Shostak. "And our galaxy, the Milky Way, has at least 100 billion stars. Some planets going around these stars might be similar to Earth."

    In the past, it was hard to look for signs of intelligent life in the universe. But now, powerful telescopes (高倍望远镜) allow scientists to discover smaller planets. These planets might have intelligent life.

    Have beings from space already visited Earth? "Probably not," says Shostak. However, intelligent beings may contact us in other way, such as radio signals (信号). In fact, they may be trying to communicate with us now, but we don't have the right tools to receive their messages. However, this is changing. By 2025, we could make contact with other life forms in our universe and we might help each other.