A lot of people are interested in sea animals, especially the ones that are beautiful and smart. Although some are wild, and can be deadly, each is also unique in its own way. Whales, sharks and dolphins are the main subjects of sea-animal research, with dolphins standing out from whales and sharks for their friendly behavior with humans. No doubt the desire to learn some interesting things about dolphins has led you to this article, and you too are eager to know more about these sea creatures.      It is sometimes believed that Dolphins have been evolved from land mammals  . Among sea mammals, dolphins are the most advanced in intelligence. You may be surprised to learn that they are close  s of camels and cows. The debate on the origin of the dolphin is an unending one, however. Some believe that they evolved from land-based hoofed   mammals, others believe that they evolved from other different kinds of mammals many millions of years ago. There are about 32 types of dolphins that live in salt water, each unique in its color1 and body shape. Five other types live in fresh water.       A grown-up dolphin eats nearly 20 to 22 kilos of fish every day. The eating habits of dolphins depend on where they live, and on the season. Seasons in which fish are abundant are like party time for dolphins. Dolphins decide how much they are going to eat based on the fat content of the fish available. They've a good sense of understanding about their hunger.      The social skills and intelligence of dolphins make them very attractive for zoos and aquariums, where they are often trained to show off their diving skills. Dolphins also communicate with each other by special sounds. Scientists like to research dolphins mainly because   _  . A) they are friendly to humans B) they have good diving skills C) they have unique bodies D) they are beautiful and clever
A

Our plan was to drive into Cambridge, catch the 7:34 train to Liverpool Street Station, then to separate and meet again for lunch. We should have arrived at Liverpool at 9:19, but due to a typical London fog, the train had to move along so slowly that it was not until 10:30 that it got there. In spite of our late arrival, Joan, my wife's sister, decided that she would go to see the Crown Jewels in the Tower of London while we went shopping. It was only after her sister had disappeared into the fog that my wife realized that we hadn't decided where we should meet for lunch. Since I had our three tickets for the concert in my pocket, this was indeed a problem. There seemed to be nothing we could do except taking a taxi to the Tower of London, and try to find her there. Needless to say, we didn't find her. It was now one o'clock, and the concert began at 2:30. "Perhaps she will think of waiting outside the concert hall," suggested my wife hopefully. By this time the fog was so thick that road traffic had to stop, and the only way to get there was by underground railway. Hand in hand we felt our way along the road to where we thought the nearest station should be. An hour later we were still trying to find it. Just as I was about to lose my temper completely when we met a blind man tapping his way confidently through the fog. With his help we found Tower Hill tube station just fifty yards down the road. By now it was far too late even to try to get to the concert hall before the performance began at 2:30, so we decided to return to Cambridge. It took seven long hours instead of the usual two to make that journey. Nor were we able to get any food and drink on the train. Tired and hungry we finally reached home at ten, opening the door to the sound of the telephone bell. It was Joan; she had seen the Crown Jewels, had managed to get another ticket for concert, and had had a wonderful dinner at a restaurant near the hotel where she decided to stay for the night. Now she was ringing to discover whether we had had an... It's quite clear that for Joan the trip to London had been   _  . A) spilt by the fog B) quite tiring C) rather disappointing D) very enjoyable
D

Mark Thompson, the BBC's director general, is expected to announce on Thursday that the BBC will quit its entire west London home -- possibly selling the land to Chelsea football club -- as part of main plans that will see more staff moved out of the capital to Salford and elsewhere. The move is at the heart of the BBC's long-awaiting cost-cutting strategy which will see nearly 2,000 more jobs going at the public broadcaster, and some original programming,such as daytime shows on BBC2, _ to save money. Several thousand people are employed at the west London sites,including Thompson himself and the bosses of all the BBC's television channels.The employees are expected to be relocated to Broadcasting House in central London, Salford, or elsewhere. The BBC has been broadcasting at various locations in the Shepherd's Bush area since moving into Lime Grove in 1949.It then switched to the Television Centre in 1960,and more modern offices at nearby White City.But it is now open to selling the site, and the broadcaster has had talks about attracting Premier League clubs Chelsea or Queen's Park Rangers as buyers.Both clubs are looking for new homes. Earlier leaks suggest that the BBC will seek to cut spending on sports where the corporation has already decided to share coverage of Formula 1 with Sky TV -- and imports,such as Mad Men and The Killing.BBC4 is expected to focus on "arts and archive ", but Thompson has long ruled out closing any channels or radio stations.BBC1 and Radio 4 will be protected,but there are expected to be some cuts to local radio programs, which will see stations share shows outside breakfast and drive-time hours. The corporation is already committed to remove TV Centre by 2015, but because parts of the building are listed, the football clubs have expressed an interest in the BBC's White City offices instead,which could be knocked down. The White City building is where Thompson and the broadcaster's commercial division, BBC Worldwide, are based. BBC sources say the 2,500 job losses being... From the passage,we can learn that   _  . A) the BBC will cover Formula 1 on its own as usual B) the football clubs are likely to buy some of the BBC's offices C) the BBC's commercial division will be open to selling the sites D) the BBC's offices are all in the White City of London

B