Read the article and select the best answer. Article: The German shepherd runs off and noses around in the grass of Kenya's Laikipia Plateau. "OK, Oakley," the dog's handler orders, "Find it!" Oakley sniffs until he comes to a bush, then stops, sits, and looks up at his handler. She bends to see what he has found: the waste of an endangered African wild dog. "Good dog!" she praises. The handler pulls a tennis ball from her pocket. Oakley jumps for his reward. "He doesn't actually want the waste," says Aimee Hurt, a founding member of the U.S.-based group Working Dogs for Conservation. Hurt is in Kenya to train both Oakley and his handler. "He finds it so he can play with his ball. We're the ones who want the waste." Detection dogs are sometimes taught to locate actual animals. Black-footed ferrets have been studied with their help. But more often the dogs learn to locate the waste of creatures such as bears, wolves and mountain lions. What the dogs find provides scientists with data about a species. Scientists can use the DNA collected from animal waste to identify individuals, sex, and population sizes -- all without ever seeing the animal itself. "It can take years to gather this kind of information if you have to trap animals," Hurt explains. Waste analysis might make a huge difference when wild species are accused of attacking domestic livestock . Hurt says, "A good detection dog will find the waste so we can see what the animal is actually eating." This may help reduce problems between people and wildlife. Question: Which of the following is TRUE according to the passage? Options: A: Trapping animals is not difficult. B: People are making efforts to protect the environment. C: Detection dogs attack domestic livestock frequently. D: Collecting animal waste is a good way to gather information.
D

Read the article and select the best answer. Article: Surveys of American teenagers find that about half of them do not get enough sleep on school nights. They get an average of 60 to 90 minutes less than experts say they need. Experts say teens are biologically programmed to go to sleep later and wake up later than other age groups. Yet many schools start classes as early as seven in the morning. As a result,many students go to class feeling like Danny,16 years old. He plays two sports,lacrosse and football. He is an active teen--except in the morning. DANNY:"Getting up in the morning is pretty terrible. I'm just very out of it and tired. And through first and second period I can hardly stay awake." Michael Breus,a clinical psychologist with a specialty in sleep disorders says:"These aren't a bunch of lazy kids--although,you know,teenagers can of course be lazy. These are children whose biological rhythms,more times than not,are off."Teens,he says,need to sleep eight to nine hours or even nine to ten hours a night. He says sleepy teens can experience a form of depression that could have big effects on their general well-being. It can affect not just their ability in the classroom but also on the sports field and on the road because any tired driver is dangerous,especially a teenager with a lack of experience. So what can schools do about sleepy students?The psychologist says one thing they can do is start classes later in the morning. Eric Peterson,head of St.George's School in the northeastern state of Rhode Island,says,"In the end,schools ought to do what's the right thing for their students,first and foremost."And he wanted to see if a 30-minute delay would make a difference. did. Question: What can you infer might follow the passage immediately? Options: A: Some positive changes in St.George's school. B: Some complaints from teachers and parents. C: Some tips on how to help students foremost. D: Some unexpected outcome of the delay.
A

Read the article and select the best answer. Article: In 2013, a report from The Nero England Journal of Medicine showed that increased body weight is related to the death rate for all cancers. This is based on a study involving about 900,000 people, spanning many years. The study, started in 1992 by the American Cancer Society, included men and women from all 50 states. The youngest participants were 30 years old, and the '8verage age was 57. By December 2008, 24% of the participants had died, just a quarter of them from cancers. In analyzing the results, researchers attempted to take account of such potential factors as smoking drinking alcohol, taking aspirin and a wide variety of other factors that might otherwise affect the results. The results are clear the more you weigh, the greater your risk of dying of cancer will be (up to 52% higher for men and 62% for women). In men as well as women, the only cancers that did not have a strong connection with weight were lung cancer and-brain cancer. For women, the strongest correlation with weight was uterine cancer ,which is 6.5 times higher for women with a BMI(Body Mass Index)of 40 or more. For men, it was liver cancer, which is 4.5 times higher in most obese men. Smokers tend to be more successful in keeping weight off than non-smokers ,slightly reducing the risk ,But many of them don't have good lungs .Thus ,in another way ,they also face risks. As for why extra weight leads to excess cancer death rate ,there's no clear agreement .But the decrease in vitamin D in obese people seems a likely factor .Vitamin D is known to have a role in preventing cancer .Also, there is a simple fact that obesity makes the management of cancer more difficult .Although for now there is no simple answer to why obesity increases a person's cancer risk ,all we know for certain is that the risk is real. Question: The author develops the passage mainly through _ . Options: A: time order B: space order C: analysis and comparison D: figures and examples,
C