The need to feed a growing population is putting much pressure on the world's supply of water. With 97% of the world's water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage(短缺)seems strange to someone fortunate enough to live in a high rainfall country, many of the world's agricultural industries experience constant water shortages.

    Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution(重新分配)are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements. This is particularly troubling for countries with agricultural industries in areas dependent on irrigation. In Texas, farmers' overuse of irrigation water has resulted in a 25% reduction of the water stores.

    In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.

    Saudi Arabia's attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    Shoppers in the UK are spending less money on toilet paper to save money, research has shown.

    Penny saving UK consumers choose cheaper products from discounters such as Aldi and Lidi rather than expensive alternatives.

    This has wiped 6% off the value of the soft tissue paper market in the UK. It has reduced from £1.19 billion in 2011 to £1.12 billion in 2015, according to a new report from market research company Mintel. Furthermore, the future of the market looks far from positive, with sales expected to fall further to £1.11 billion in 2016.

    In the last year alone, despite an increase in the UK population and a rise in the number of households, sales of toilet paper fell by 2%, with the average household reducing their toilet roll spending from £43 in 2014 to £41 in 2015.

Overall, almost three in five people say they try to limit their usage of paper – including facial tissue and kitchen roll    to save money. “Strength, softness and thickness remain the leading signs of toilet paper quality, with just a small part of consumers preferring more expensive alternatives, such as those with flower patterns or perfume,” said analyst Jack Duckett. “These extra features are considered unnecessary by the majority of shoppers, which probably reflects how these types of products are typically more expensive than regular toilet paper, even when on special offer.”

    While consumers are spending less on toilet paper, they remain particular about it when it comes to paper quality. One in 10 buyers rank toilet rolls made from recycled paper among their top considerations, clearly showing how overall the environment is much less of a consideration for shoppers than product quality. In a challenge for makers, 81% of paper product users said they would consider buying recycled toilet tissue if it were comparable in quality to standard paper.

    The writer Margaret Mitchell is best known for writing Gone with the Wind, first published in 1936. Her book and the movie based on it, tell a story of love and survival during the American Civil War. Visitors to the Margaret Mitchell House in Atlanta, Georgia, can go where she lived when she started composing the story and learn more about her life.

    Our first stop at the Margaret Mitchell House is an exhibit area telling about the writer's life. She was born in Atlanta in 1900. She started writing stories when she was a child. She started working as a reporter for the Atlanta Journal newspaper in 1922. One photograph of Ms. Mitchell, called Peggy, shows her talking to a group of young college boys. She was only about one and a half meters tall. The young men tower over her, but she seems very happy and sure of herself. The tour guide explains: “Now in this picture Peggy is interviewing some boys from Georgia Tech, asking them such questions as 'Would you really marry a woman who works?'

    And today it'd be 'Would you marry one who doesn't?' ”

    The Margaret Mitchell House is a building that once contained several apartments. Now we enter the first floor apartment where Ms. Mitchell lived with her husband, John Marsh. They made fun of the small apartment by calling it “The Dump”.

    Around 1926, Margaret Mitchell had stopped working as a reporter and was at home healing after an injury. Her husband brought her books to read from the library. She read so many books that he bought her a typewriter and said it was time for her to write her own book. Our guide says Gone with the Wind became a huge success. Margaret Mitchell received the Pulitzer Prize for the book. In 1939 the film version was released. It won ten Academy Awards, including Best Picture.

    Watching some children trying to catch butterflies one hot August afternoon, I was reminded of an incident in my own childhood．When I was a boy of 12 in South Carolina, something happened to me that cured me forever of wanting to put any wild creature in a cage.

    We lived on the edge of a wood, and every evening at dusk the mockingbirds would come and rest in the trees and sing. There isn't a musical instrument made by man that can produce a more beautiful sound than the song of the mockingbird.

    I decided that I would catch a young bird and keep it in a cage and in that way would have my own private musician.

    I finally succeeded in catching one and put it in a cage. At first, in its fright at being captured, the bird fluttered about the cage, but eventually it settled down in its new home. I felt very pleased with myself and looked forward to some beautiful singing from my tiny musician.

    I had left the cage out on our back porch, and on the second day of the bird's captivity(囚禁) my new pet's mother flew to the cage with food in her mouth. The baby bird ate everything she brought to it. I was pleased to see this. Certainly the mother knew better than I how to feed her baby.

    The following morning when I went to see how my captive was doing, I discovered it on the floor of the cage, dead. I was shocked! What had happened! I had taken excellent care of my little bird, or so I thought.

    Arthur Wayne, the famous ornithologist, happened to be visiting my father at the time, hearing me crying over the death of my bird, explained what had occurred. “A mother mockingbird, finding her young in a cage, will sometimes bring it poison berries. She thinks it better for her young to die than to live in captivity.”

    Never since then have I caught any living creature and put it in a cage. All living creatures have a right to live free.

    I became a magician by accident. When I was nine years old, I learned how to make a coin disappear. I'd read The Lord of the Rings and gone into the adult section of the library to be buried in fantasy literature but young enough to still hold out hope that you might find a book of real, actual magic in the library. The book I found taught basic techniques, and I tried to practice.

    At first the magic wasn't any good. It was just a trick—a bad trick. I spent hours each day running through the secret moves in front of the mirror. I dropped the coin over and over, a thousand times in a day, and after two weeks my mom got a carpet and placed it under the mirror to muffle (消音) the sound of the coin falling again and again.

    One day I made the coin disappear on the playground. We had been playing football and were standing in the field behind the school. A dozen people were watching. I showed the coin to everyone. Then it disappeared. The kids screamed. Everyone went crazy.

    A few years later, I staged an underwater escape in the river that flowed through the middle of the campus of the University of Iowa, where I went to school. I stood on a boat in the middle of the river wearing nothing but biking shorts. The sky was dead and gray, and the water was cold at the surface, and colder in the depths below.

    Technically, I succeeded. I jumped into the water, sank to the bottom, and escaped from the locks and the chains before swimming to the surface. But it didn't feel like a success.

    It's school time again! You're probably feeling excited and maybe a little sad that summer is over. Some kids feel nervous or a little scared (害怕的) on the first day of school because of all the new things: new teachers, new friends, and even a new school. Luckily, these "new" worries only stick around for a little while. Let's find out more about going to a new school.

    Most teachers kick off the new school year by introducing themselves and talking about all the stuff you'll be doing that year. Some teachers give students a chance to tell something about themselves to the rest of the class, too. When teachers do the talking on the first day, they often go over classroom rules and school rules so you'll know what's allowed and what's not. Please pay close attention.

    You might already know a lot of people in your classes on the first day, but it's a great day to make new friends, so try to say hello to kids you know and new ones that you don't. Make the first move and you'll be glad, and so will your new friends!

    Seeing friends you haven't seen in a while can make the first day a good one. You can make the day feel special by wearing clothes that you really like. Maybe you got a great T-shirt on one of your vacations, or a pair of sneakers (运动鞋). It also can make you feel good to be prepared and have all the things you need, such as pencils, folders, and whatever else you'll be needing. But make sure that you pack them the night before in case you don't have time in the morning.