Read the article and select the best answer. Article: On a cool summer night in Wyoming, Dean Biggins waits patiently in his truck. Suddenly, Biggins, a wildlife biologist, spots a pair of eyes in the distance. Baggins can't believe his luck: He's just caught sight of a black-footed ferret --one of the world's rarest animals. Just over a century ago, hundreds of thousands of black-footed ferrets lived on the grasslands in North America known as the prairie. But the animals died off as prairie dog disappeared. Black-footed ferret depend on prairie dogs for both food and shelter. After a ferret has eaten a prairie dog, it moves into the animal's burrow . When cattlemen started setting up ranches on the prairie in the early 1900s, they thought prairie dogs, which eat grass, might compete with their cattle and sheep for food. To make sure that didn't happen, they killed off billions of prairie dogs. As prairie dog populations dropped, black-footed ferrets disappeared. By 1979, researchers couldn't find any ferrets and declared the species extinct. Then, two years later, a small group was discovered. Although scientists were excited about the discovery, it soon became clear that the ferrets were in danger. A disease called sylvatic plague was killing the ferrets. Soon, just 18 ferrets remained. "To help the species survive, the researchers put all the ferrets in cages in 1986 and began raising them," says Randy Matchett, a wildlife biologist. To help the black-footed ferrets learn survival skills, wildlife biologists put them through a process called preconditioning. Researchers build a fence around old prairie dog burrows and put the ferrets in them when they are a couple of months old. While the animals get used to their new home, researchers feed them live prairie dogs so they can practice hunting. "Now about 1,000 black-footed ferrets are back in the wild. Despite their amazing comeback, black-footed ferrets aren't out of the woods yet," says Matchett. Sylvatic plague is still a threat, and ranchers still don't want too many prairie dogs on their land. "We... Question: How do scientists help the ferrets? Options: A: They take measures to stop the disease spreading. B: They call on people to stop hunting the animals. C: They set ferrets free when they are two months old. D: They train the animals so they can survive in the wild.
D

Read the article and select the best answer. Article: To the untrained eye it might seem like just a bit of a monkey trick. But when Milly the mandrill (, ) covers her face with her hand she is actually sending a serious message to her fellows: "Leave me alone!" Experts believe the 15-year-old mandrill invented the gesture to warn other monkeys at Colchester Zoo to give her some space. And, surprisingly, the signal has been picked by other members of the group, who use it when they too require _ . Biologist Mark Laidre believes the behavior is evidence of social culture among the mandrills. Importantly, the sign language is unlikely to have been influenced by human activities because mandrills do not copy humans. Mr. Laidre expects further research will uncover other monkeys using cultural gestures -- the ability to communicate with the hands in a meaningful way. "By covering their eyes with their hands, possibly conveyed to others that they wanted to be left alone and this message may have been respected as a 'do not disturb' sign," said Mr. Laidre. While the hand is in place, other monkeys are not likely to approach or touch the monkey. Those who rank lower in the social order also use the technique to avoid attacks from more powerful group members. As the discovery appears to be unique to Colchester Zoo, it suggests it is a local phenomenon that arose naturally in the community of 25 mandrills. Curator Sarah Forsyth said: "We believe Milly made up the signal and over the past five years some of the younger mandrills have picked it up. We're not sure why she started doing it but it could be as simple as 'I can't see them, so they can't see me'. It really does show you how intelligent mandrills are." Question: According to Mark Laidre, _ . Options: A: human activities affect mandrills' sign language B: animals are slow in picking up information C: mandrills' social culture has nothing to do with humans D: mandrills are the largest species of monkey in the world
C

Read the article and select the best answer. Article: It may help you to know that there is no such thing as a perfect speech.At some point in every speech, every speaker says something that is not understood exactly as he has planned.Fortunately, the moments are usually not obvious to the listeners. Why ? Because the listeners do not know what the speaker plans to say. They hear only what the speaker does say. If you lose your place for a moment, wrongly change the order of a couple of sentences, or forget to pause at a certain point, _ .When such moments occur, don't worry about them. Just continue as if nothing happened. Even if you do make an obvious mistake during a speech, that don't really matter. If you have ever listened to Martin Luther King's famous speech - " I have a dream", you may notice that he stumble his words twice during the speech.Most likely, however, you don't remember.Why? Because you were fixing your attention on its message rather than on his way of speech-making. People care a lot about making mistakes in a speech because they regard speech-making as a kind of performance rather than as an act of communication. They feel the listeners are like judges in an ice-skating competition.But, in fact, the listeners are not looking for a perfect performer. They are looking for a well-thought-out speech that expresses the speaker's ideas clearly and directly.Sometimes a mistake or two can actually increase a speaker's attractiveness by making him more human. As you work on your speech, don't worry about being imperfect.Once you free your mind of this, you will find it much easier to give your speech freely. Question: You don't remember obvious mistakes in a speech because _ . Options: A: your attention is on the content B: you don't fully understand the speech C: you don't know what the speaker plans to say D: you find the way of speech-making more important
A