阅读理解。阅读下列短文, 从给的四个选项 (A、B、C和D) 中, 选出最佳选项。

     Isaac Stern was  more  than a great violin player.He was one of the most honored musicians in the world.He was an international  cultural ambassador.He was a major supporter of the arts in America and in other countries.He was a teacher and activist.

     Isaac Stern was born in 1920 in what is now Ukraine.His parents moved  to  San Francisco，California the following year.His mother began teaching Isaac the piano when he was six. He began taking violin lessons after hearing a friend play the instrument.Later，he began studying music at the San Francisco Conservatory(音乐学院)．He progressed quickly.When he was 16，he played with the San Francisco Symphony Orchestra.The next year，he performed in New York City and was praised by music critics.

     During World War II ，Mr.Stern played for thousands of American soldiers.It was the first time many of them had heard classical music.After the war，he was the first American violinist to perform in a concert in the Soviet union.He also supported young musicians and cultural organizations in Israel.

    In 1979，Isaac Stern visited China.He met with Chinese musicians and students.He taught them about classical Western music.His visit was made into a film，which is called From Mao to Mozart：Isaac Stern in China.It won an Academy Award for best documentary film.

     In 1984，Isaac Stern received the Kennedy Center Honors Award for his gifts to American culture through music.He expressed his thoughts about the part that music plays in life.He said he believed that music makes life better for everyone，especially children.

     Mr.Stern supported and guided younger classical musicians.They include violinists Itzhak Perlman and Pinchas Zukerman，cellist Yo­Yo Ma，and pianist Yefim Bronfman.

     Isaac Stern died in 2001 at the age of 81.He was a major influence on music in the 20th century.He leaves the world richer with his many recordings.

    There are 5.25 trillion pieces of plastic trash in the world's oceans, and each year, 8 million tons of plastic are added to the figure. Though the oceans seem vast enough to stomach a lot of plastic, the level of waste is starting to reach a crisis point: According to a new report by the Ocean Conservancy, by 2025, the ocean could contain one ton of plastic for every three tons of finfish.

All these floating bits of plastic not only disrupt marine ecosystems, but they also poison the global supply of seafood. “It's reaching crisis proportions,” says Andreas Merkl, CEO of the Ocean Conservancy. “Plastic breaks down into small pieces that look like plankton and is eaten by everyone from plankton to whales.” Plastic acts as a pollution sponge in the ocean, so when wildlife swallow pieces, the plastic might as well be a poison pill.

    The new report calls for a focus on improving waste management systems in a handful of developing countries that are most responsible for the plastic leakage into the ocean. China, Indonesia, the Philippines, Thailand and Vietnam contribute more than half of the oceans' plastic since their waste facilities hasn't kept up with rapid industrialization.

    On average, only about 40% of waste in these countries is actually picked up for disposal. But it's not just uncollected waste floating around-though that is three-fourths of the problem. The other quarter of the oceans' plastic came from post-collection activities. Even when a waste management company picks up waste to landfill it, poorly equipped landfills or illegal dumping mean that trash still ends up in the ocean.

    But how can countries stop the leakage of waste into the ocean? The Ocean Conservancy report suggests five “levers”: waste collection services, closing the leakage points within the collection system, gasification and burning of waste, and recycling facilities. The average waste ends up as litter. Just by expanding collection systems and plugging up their leakage points, the report says plastics leakage could by cut by 50% by 2020.

    It's not just an environmentalist's daydream. Coca-Cola and Dow Chemical, along with some other multinational companies have joined forces with Ocean Conservancy to fight ocean pollution. “We're committed to working toward a future of a plastic-free ocean. Companies don't make plastic with the intent of it ending up in the ocean, and we acknowledge the strong role industry must play in order to help eliminate ocean plastic waste by 2035.” Says Dow Packaging and Speciality Plastics' global sustainability director in a press release.

    Merkl emphasized that the countries can't recycle their way out of the problem. Only about 20% of the waste is valuable enough to be worth recycling: the rest, needs to be sent to sanitary landfills or waste-to-energy plants. “You have to concentrate on the fundamentals of waste management,” he says. And while building landfills and incinerators(焚化炉)across these developing countries might not be pretty, it's far more environmentally friendly than letting waste slide into the world's oceans.

    Who could have imagined that a treadmill(跑步机)on wheels would one day become a thing? Lopifit is an unusual means of transportation that allows you to power an electric bicycle by walking on a treadmill.

    Lopifit founder Bruin Bergmeester says it all started when he asked himself the question. "How can I use a treadmill outdoors?" He eventually came up with a design, to which he added an electric engine, and Lopifit was born. The treadmill bicycle is similar to a typical electric bicycle in that the motor only works when the rider puts power in as well. The Lopifit senses it when you walk on the treadmill and uses the motor to turn a drive chain at the back part of the treadmill, helping you reach a top speed of 17 miles per hour.

    To use the Lopifit, simply turn on the battery and use your feet to slide the treadmill backwards and activate (激活) the motor. Then get on and enjoy the ride! If you need speed, just walk on the treadmill, and if you want to coast, all you have to do is stay still and admire the view. To stop, you have two hand brakes available.

    The Lopifit first hit the streets in 2014 and, unsurprisingly, became an instant hit. That was actually quite challenging for the company, because it started get inquiries and calls for orders, but it was nowhere near ready for mass production. The unique treadmill bicycle became available this year, and Lopifit is struggling to keep up with demand, despite the high price tag of $ 2,115.

    But despite having a very loyal fan-base of so-called Lopifitters, the creative means of transportation also has naysayers who simply consider the invention stupid and unnecessary. They basically believe that if you're going to walk, you might as well do it the old-fashioned way. But the Lopifit does have the unique advantage of helping you walk really fast without breaking a sweat, or walking at cycling speed, if you will.

    Being able to land safely is a critically important skill for all flying animals. Comparatively speaking, ground living animals face no particular challenge when they need to stop running or crawling, while flying animals move at much higher speed, and they must be careful about how they land. Hitting the ground, or even water, at full flight speed would be quite dangerous. Before touching down, they must decrease their speed in order to land safely. Both bats and birds have mastered the skill of landing, but these two types of flyers go about it quite differently.

    In the past it was believed that, in terms of flying mechanics, there was little difference between bats and birds. This belief was based only on assumption, however, because for years nobody had actually studied in detail how bats move their wings. In recent years, though, researchers have discovered a number of interesting facts about bat flight. Bats are built differently from birds, and their wings are made up of both their front and hind limbs (肢体). This makes coordinating (协调) their limbs more difficult for bats and, as a result, they are not very good at flying over longer distances. However, they are much better at the ability to adjust themselves: a bat can quickly change its direction of flight or completely reverse it, something a bird cannot easily do.

    Another interesting characteristic of bat flight is the way in which bats land-upside down! Unlike birds which touch down on the ground or on tree branches, bats can be observed flying around and then suddenly hanging upside down from an object overhead. One downside to this landing routine is that the bats often land with some force, which probably causes pain. However, not all bats hit their landing spots with the same speed and force; these will vary depending on the area where a bat species makes its home. For example, a cave bat, which regularly lives on a hard stone ceiling, is more careful about its landing preparation than a bat more accustomed to landing in leafy treetops.

    Are you interested in country music? I like it very much! It will take me away for a while after I am tired. The guitars and songs will take me to mountains and fields. Country music usually talks of everyday life and feelings. It's the spirit of America, easy to understand, slow and simple. Country music developed in the Southern United States. It was the folk music of American countryside. Many of songs tell about the lives of farmers. They talk about love, crops or death.

    The life of the countryside can be hard, so the words in country music are often sad. At first, people played the music only at family parties. But it became more popular later. In the 1920s, people played country songs on the radio, and they made them into records. When people in the countryside moved to towns and cities to look for work, they took their music with them. Country music continued to change and became popular across America. John Denver was one of America's most famous country singers in the 1970s. His song "Take Me home, Country Roads" is well-known and people still play it today.

As the COVID-19 pandemic hit hard, fishermen watched their markets dry up. Restaurants-normally major fish buyers-closed or cut back orders significantly. Fishermen weren't sure if they were going to get paid for what they fished.

Meanwhile as people lost jobs, food banks started to see a great demand for services. Things were getting desperate, with long lines for food assistance in many states.

Out of these dual crises, a new idea was born. Food assistance programs across the country have started connecting with local fishermen to stock up on local seafood, many for the first time. And the arrangement seems to be helping the fishermen, the economy and those in need of healthy food.

According to Catherine D' Amato, CEO of the Greater Boston Food Bank, the network usually keeps four or five weeks of food on hand in case of emergencies. The pandemic hit, and "we found ourselves below one week of stock and going down rapidly," she says. That's because the food bank normally distributes about I million pounds of food a week, and that became 2.5 million pounds of food a week, D' Amato says. While Congress and the states have increased funding and donations for food banks during the pandemic, it hasn't been enough.

"For many years, we have been wanting to be able to work with organizations in the fishing industry," D' Amato says. But it's complicated. Fishermen catch a lot of big fish, and food banks who might take it need the products to be cut small and easy to use for customers. It also has to be fish they know and recognize. The barriers have been too high in many places to make it work. But this spring, the state department of agriculture connected the food bank with some grant makers. They talked to some local fishermen about developing a traditional New England fish soup.

The grants paid fishermen for their catch and provided money for a local manufacturer to process, freeze and deliver the soup to food banks in family-size servings. The soup is helping to feed families and keep fishermen fishing. The fishermen hope to sell it in stores soon, and Damato hopes to purchase more soup and expand into new seafood products for her customers.