阅读下列短文，从每题所给的四个选项(A、B、C和D)中选出最佳选项。

    If cars had wings，they could fly and that just might happen，beginning in 2011.The company Terrafugia，based in Woburn，Massachusetts，says it plans to deliver its car­plane，the Transition，to customers by the end of 2011.

    “It's the next ‘wow' vehicle，” said Terrafugia vice president Richard Gersh.“Anybody can buy a Ferrari，but as we say，Ferraris don't fly.”

    The car­plane has wings that unfold for flying－a process the company says takes one minute－and fold back up for driving. A runway is still required to take off and land.

    The Transition is being marketed more as a plane that drives than a car that flies，although it is both. The company has been working with FAA to meet aircraft regulations，and with the National Highway Traffic Safety Administration to meet vehicle safety regulations.

    The company is aiming to sell the Transition to private pilots as a more convenient and cheaper way to fly. They say it saves you the trouble from trying to find another mode of transportation to get to and from airports：You drive the car to the airport and then you're good to go. When you land，you fold up the wings and hit the road. There are no expensive parking fees because you don't have to store it at an airport－you park it in the garage at home.

    The car­plane is designed to fly primarily under 10,000 feet. It has a maximum takeoff weight of 1,430 pounds，including fuel and passengers. Terrafugia says the Transition reduces the potential for an accident by allowing pilots to drive under the bad weather instead of flying into marginal(临界的) conditions.

    The Transition's price tag：$194,000.But there may be additional charges for options like a radio，a transponder or a GPS. Another option is a full­plane parachute.

    “If you get into a very awful situation，it is the necessary safety option，” Gersh said.

    So far，the company has more than 70 orders with deposits. “We're working very closely with them，but there are still some remaining steps，” Brown said.

    It's true that quite a few most respected scientific authorities have confirmed that the world is becoming hotter and hotter. There^'s also strong evidence that humans are contributing to the warming. Countless recent reports have proved the same thing. For instance, a 2010 summary about the climate science by the Royal Society noted that: The global warming over the last half - century has been caused mainly by human activity.”

    You may not believe that humans could change the planet's climate, but the basic science is well understood. Each year, billions of tons of greenhouse gases are released into the atmosphere because of human activity. As has been known for years, these gases hold heat that would otherwise escape to space, wrapping the planet in an invisible blanket.

    Of course, the earth's climate has always been changing due to “natural” factors such as volcanic eruption or changes in solar, or cycles concerning the Earth's going around the sun. According to the scientific research, however, the warming observed by now matches the pattern of warming we would expect from a build - up of greenhouse gas in the atmosphere - not the warming we would expect from other possible causes.

    Even if scientists did discover another reasonable explanation for the warming recorded so far, that would give birth to a difficult question. As Robert Henson puts it: “If some newly discovered factor is to blame for the climate change, then why aren't carbon dioxide and the other greenhouse gases producing the warming that basic physics tells us they should be?”

    The only way to prove with 100% certainty that humans are responsible for global warming would be to run an experiment with two identical Earths-one with human influence and one without. That obviously isn't possible, and so most scientists are careful not to state human influence as an absolute certainty.

    Americans, especially the millennials（千禧一代）, are always glued（固着于）to their phones. A common day of the average university student in America starts off like this: an alarm clock wakes you up, which is quickly followed by checking social media such as Twitter and Facebook. Once in classes, you are again attracted by your buzzing phone and access to the Internet rather than pay attention to the lecturing professor. Then you have lunch with some friends, only to look up from your screen to realize that no one has said a word in five minutes and instead all are looking at their phones. Once the day ends, you can't help checking all forms of social media again before finally being able to shut your eyes only to repeat this vicious cycle the next day.

    Cyberbullying（网络霸凌）, a concept unknown before, is now in fashion. Many of the millennials are using the Internet to make jokes about others to points of extremes. The Internet gives cowards bravery; people feel like their actions and words have no bad results because they cannot see the ache it causes another.

    Millennials also think that whatever information shows up on their screens must be taken as truth, whether the material is reliable（可靠的）or not.

    Social media is not all bad, however. People are still able to use social media to connect with friends and family who live a great distance away. With a few clicks of a button, someone could make another person smile, or give words of hope and encouragement to a friend in need, or even help repair a broken relationship. Cyberspace is a vortex（漩涡）that is easy to get caught up in, but we must find a balance to keep both feet in reality while traveling across the online world.

    Mrs Smith trembled(颤抖)with excitement when she was told her fortunes(命运). "Somebody is coming home to you, " Mrs Gray said slowly. "He's carrying a rifle(步枪)on his back and he's almost there."

    Mrs Smith felt as if she could hardly breathe. "And there he is!"Mrs Gray cried, pointing to the road. They all rushed to the door to look.

    A man in a blue coat, with a gun on his back, was walking down the road toward the Smith farm. His face was hidden by a large pack on his back.

    Laughing and crying, Mrs Smith grabbed(抓住)her hat and her children and ran out of Mrs Gray's house. She hurried down the road after him, calling his name and pulling her children along with her. But the soldier was too far away for her voice to reach him.

    When she got back to their farm, she saw the man standing by the fence. He was looking at the little house and the field of yellow wheat. The sun was almost touching the hills in the west. The cowbells rang softly as the animals moved toward the barn(畜棚).

    "How peaceful it all is, "Private Smith thought." How far away from the battles, the hospitals, the wounded and the dead. My little farm in Wisconsin. How could I have left it for those years of killing and suffering?"

    Mrs Smith hurried up to her husband. Her feet made no sound on the grass, but he turned suddenly to face her. For the rest of his life, he would never forget her face at that moment.

    "Emma!" he cried.

    The children stood back watching their mother kissing this strange man. He saw them, and kneeling down, he pulled from his pack three huge red apples. In a moment, all three children were in their father's arms. Together, the family entered the little unpainted farmhouse.

    Later that evening, after supper, Smith and his wife went outside. The moon was bright, above the eastern hills. Sweet, peaceful stars filled the sky as the night birds sang softly.

    His farm needed work. His children needed clothing. He was no longer young and strong. But he began to plan for next year. With the same courage he had faced the war, Private Smith faced his difficult future.

    When Mackenzie Foy got the call from film director Lasse Halls telling her that she'd landed the role of Clara in the newDisney film The Nutcracker and the Fоur Rеаlmѕ, she said "yes immediately. "I was just excited to go on a new adventure," Foy told the Evening Standard. Indeed, when many actors and actresses choose to appear in films simply for the fame and exposure, Foy, the17-year-old US actress, does it for the "adventure".

    It's true that every movie Foy has ever been in is an adventure. In The Twilight Saga: Breaking Dawn for example, the then 11-year-old Foy plays a half-human-half-vampire girl who has a superpower. In Interstellar, then 14, plays the daughter of a scientist who travels across the universe to try to find ways to save human beings from destruction. And now, in The Nutcracker and the Four Realms, which will be released in Chinese cinemas on November 2, Clara is going on yet another exciting journey. This time, she allows a doll that her parents give her as a Christmas gift into a strange world.

    Foy likes excitement in real life, too. In fact, she has a first-degree black belt in tae kwon do( MY y ilÏ)."I am dying to do an action movie," she told VanityFair. "I can do my own stunts." And not happy with simply being in front of the camera, Foy dreams of trying something new one day. I want to be a director once I finish high school," she told the Evening Standard. "I want to make films that will make people end up looking at the world in a different way, so that they will feel inspired and learn something new."

    For many of us, summertime means road trips to the beach or mountains, or at the very least some additional dust and bird poop on the exterior of our vehicles. The extra dirt leads us to do one of two things: wash our car in the driveway or head to the car wash. But which choice is better for the environment?

    The main concerns with either choice are the amount of fresh water being used and the types of chemicals used to remove the dirt. Both of these concerns can be closely monitored when washing the car at home, says Katy Gresh, spokeswoman for the Southwest Region of the Pennsylvania Department of Environmental Protection. She advises car owners to put aside a set amount of water for the entire wash. "It's just like brushing your teeth," she says, "You don't want to leave the water running of more than you need for the job." But even following this advice comes with an environmental risk: Washing your car in the driveway or street flushes the dirty water into storm drains.

    John Schombert, executive director of 3 Rivers Wet Weather, his organization works to educate the public about storm sewers (下水道) and water runoff, keeping this untreated water from entering the Allegheny region's waterways. "We ask people to, consider washing their cars on lawns or other permeable (透水的) surfaces where the water gets absorbed," Schombert says. "Soil can break down and help filter (过滤) those things," Schombert says. "Storm sewers are not made for waste disposal." Even when car owners use natural soaps to wash their cars, which Schombert says are probably ineffective at breaking down grease anyway.

    The commercial car wash down the street knows full well the rules regarding wastewater in storm sewers. According to the International Carwash Association (ICA), professional car washes must use water reclamation systems. These mandated processes not only keep the dirty water out of storm sewers and regular water treatment systems, but they also work to reduce water usage at commercial facilities.