单项选择题

Part B
The passage below summarizes the main points of the passage. Read the summary and then select the best word or phrase from the box blow, according to the passage. You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the center.
Every morning, Allie wakes up and accompanies her friend to the washroom. She turns on the light, soaps up a washcloth, and begins cleaning her friend’s face. Is Anie an extremely devoted companion Yes! Allie is a capuchin monkey who helps her disabled friend perform everyday tasks.
Monkeys like Allie are just one of many kinds of animals that help improve--or even save--human lives. But not all animals are suited to do every job. Certain animals are "hired" for specific jobs based on their traits, or characteristics. By using different methods of conditioning (training animals to act in a particular way in response to a stimulus, or signal), humans can teach animals toper form extraordinary tasks.
Throughout history, humans have relied on animals’ traits to get certain jobs done. For example, compared with humans, dogs are "far superior at tracking down odors", says Marian Bailey, an animal behaviorist at Henderson State University in Arkansas. That’s because dogs have million of olfactory receptors, or smell nerves, in their noses.
For that reason, hunters used dogs to track down prey even in ancient Egypt. Today, dogs my be employed to sniff out illegal substances in school lockers or earthquake victims buried beneath the rabble of the collapsed building or highway.
Primates may not be good sinffers, but they can certainly lend a helping hand--or two. Monkeys are perfect helpmates for quadriplegics, people paralyzed from the neck down who are unable to use their own hands (and legs). Like humans, explains Bailey monkeys have opposable thumbs--thumbs that face the hand’s other fingers--so monkeys can pick up objects. Capuchins learn to open doors, clean up spills, and unscrew bottle tops. They can even get a sandwich out of the refrigerator and load your favorite tape into the VCR.
And speaking of VCRs, animals are even helping scientists make a videotape. Jennifer Hurley, an animal researcher at the Long Marine Lab in Santa Cruz, California, is training two sea lions to carry video cameras on their backs to record the natural behavior of whales.
So how do you get an animal employee to do its job The answer, career-training. Trainers teach the animals to obey their instructions through a process called conditioning.
Most trainers condition animals by using positive reinforcement, rewarding an animal for doing something correctly, says animal behaviorist Bailey. For example, trainers teach their dogs how to sniff out drugs by hiding a towel with the smell of drags. "Dogs love to retrieve objects so the towel becomes a reward", says Morris Berkowitz, who heads up a canine drug-sniffing program in New York.
After repeating this game of hide-and-seek many times, the dog begins to "associate the odor with a reward", says Berkowitz. When he gives the command, or stimulus, the dog seeks cot drags (it’s like learning to study hard for a tests in order to get a good grade as a reward.)
At "Helping Hands--Monkey Helpers for the Disabled", capuchin monkeys are trained twice before being teamed with a disabled human. First, monkeys are placed with a foster family to become socialized to people. For five years, families help the monkeys adapt to a human environment, so the monkeys will trust and enjoy being around people.
Taking the monkeys in when they’re four to six weeks old is important, says Bailey. "That’s when monkeys normally become socialized to other monkeys," she says.
Second, trainers at Helping Hands train the monkeys to perform specific tasks to assist a particular person. For example, a monkey may be trained to scratch an itch, or slip a floppy disc into a computer dive. Trainers reward the monkeys by using positive reinforcement, such as food, drinks.
Allie is a capuchin 16 who helps her disabled friend perform everyday tasks. Allie is a(n) 17 of many animals who can be 18 to do certain jobs. Besides monkeys, 19 and sea lions can also give people a helping 20 .
Dogs are good at 21 down prey and sniffing out 22 and 23 because they have millions of 24 in their nose Monkeys are good helper for the 25 , who cannot look after themselves. Sea lions can help scientists to record the 26 of whales because they :can 27 to the deep ocean. In addition, 28 are part of whales’ natural environment, which makes the video more 29 .
But animals cannot do the jobs 30 training. The main process of training is called 31 , which uses 32 . During the training, trainers 33 an animal for doing something 34 . For monkeys, the positive reinforcement can 35 a year before they are qualified for their jobs.