短文理解  阅读下列短文，从每题所给的A、B、C三个选项中，选出最佳选项回答问题或完成句子。

    Why is clean water so important to developing countries? A recent report shows that about 80 percent of diseases in developing countries are caused by poor water and low sanitation（卫生）conditions. In those countries, women and girls spend several hours collecting water, but often polluted, far away from their families. The polluted water more or less influences their health. In this case, there is an urgent（迫切的）need for people in developing countries to have access to（有机会或权利使用）clean water to improve their health.

    Here is a short story about Hadjara Zakari, a 12-year-old girl in Niger. Having access to clean water changed her life. She learned about the importance of hand-washing when the school first received clean water three years ago. That evening, she told her father, "You shouldn't eat with me unless you clean your hands." Her father was very angry and shouted at her, "It's not up to you to tell me what to do!"Stunned（目瞪口呆的），Hadjara sat in silence. But she knew she was right. In protest,Hadjara refused to eat dinner that night. After her father questioned Hadjara's head teacher, he understood the importance of hand-washing and his daughter's intentions（目的）. The girl really wanted her family to live longer and healthier lives.

    For people in developing countries, clean water can change many things, especially improve their health. So, from now on, let's avoid wasting water and take action to save water, which is important to people all over the world.

    There are world records at the Olympic Games. But what are the word records in animal kingdom?

    The largest and heaviest animal on earth is the blue whale. It weighs between 110 and 120 tons. Its heart is the size of a Mini Cooper, It's got the biggest mouth in the world as well. About 100 people can fit inside it. But it doesn't eat people! In fact, the biggest thing it can eat is the size of an apple.

The giraffe is smaller than the blue whale but it is also a record breaker. It's the tallest living land animal. It's got the longest neck-about 2 metres long, and it's got the longest legs-about 1.8 metres long. Drinking is difficult, but eating from the top of trees is easy! And its tongue is 50 c m long!

    The most dangerous animal in the world isn't a lion or a bear. It's an insect! The mosquitoes (蚊子) that carry malaria kill over 1 million people a year. After that, the most dangerous animal is the venomous snake. They kill 50,000 to 125,000 people a year.

     A. the mosquito           B. the giraffe                C. the blue whale

    What will our homes be like in the future? Here are some predictions:

    Want to take a shower when you get home? You'll be able to let your smart water heater(热水器) to start heating up when you're on your way home..

    Did I turn off the oven? Did I close the window? Everyone may have a moment like that. But in the future, your home will check these for you.

    In your home of the future, all of your devices (设备) can work together to make your life more comfortable. When you turn on the lights in the morning, your windows will open at the sometime. The lights will slowly turn off by themselves after the sun appears.

    Your home may have dangers. The hackers (黑客)could open your door and cause a mess at your home through your phone or other devices. Your home will tell you about it, but you can't arrive in time. So people will have to be careful of their personal information.

    For thousands of years, humans have explored(探索)the Earth. Nowadays, we are exploring space. Astronomers (天文学家) are the modern﹣day explorers, Now, many astronomers are looking for new planets and new places for humans to live in the future. But where do astronomers start looking？

    First of all, astronomers look for a star. That's because our own Earth moves around a star (the Sun). More importantly, it is the correct distance( 距离) from the Sun for heat and light. So when astronomers have found the star, they look at the planets around it. In recent years, astronomers have found nearly 400 new planets with stars. However, many of these planets are either too near to the star or too far away.

    However, if the planet is in a good position, astronomers look for three key things: water, air and rock. Water is important because all life needs water. Humans can drink it and they can also grow plants with water. And plants produce air for humans to breathe and food to eat. Rock on a planet is also important. That's because there is often water under the rock.

    After many years of scrutinizing, astronomers have found a planet that is similar to the Earth. It's Gliese 581g and it's near a star. The astronomers think it has water and rock and the average(平均的) temperature is between -31℃ and -12℃.That's cold, but not colder than Antarctica or the Arctic Circle, for example. Gliese 581g is bigger than the Earth. A year on Gliese 581g is only 37 Earth days instead of 365. But astronomers do not think these are big differences and some of them think Gliese 581g will be a new Earth. However, Gliese 58Ig is twenty light years from the Earth.

① A survey(调查) has shown that lots of people can't sleep well. Sometimes you feel tired when you wake up. You may have a headache and you feel like you could sleep for another three hours. Many things around us cause sleeplessness. Here are a few changes you can make to improve your sleep.

②Go to bed and get up at the same time. You may share the same bedroom with your sister or brother. You both must go to bed regularly(规律地) so that you don't trouble each other.

③Clean up your bedroom. A study from a university in Zhengzhou found that people with clean bedrooms usually sleep better than those with dirty and untidy rooms.

④ Get more house plants. Studies show that house plants help with reducing (减轻)stress. Also, plants such as lavender(薰衣草) and gardenias(栀子花) have smells that may help some people relax and sleep better.

⑤ Make your room dark. When light hits your eyes, it tell you not to fall asleep. In fact, we need darkness especially in the evening. So if you want your body to know that it's time to rest, turn off the lights about an hour before bedtime or wear eye masks. Your phone and your TV should also be thought of. You may also use the dark curtaıns(窗帘) to keep any outside light from going into your bedroom.

⑥Lower your bedroom temperature. The body becomes cooler at night, so lowering the temperature before bedtime can help you relax and fall asleep more quickly. The NationalSleep Foundation in a country says your bedroom should be about 16 ℃ to 19℃ for a good night's sleep.