In this task, you're given an article, a question which often contains a blank and four options (associated with "A", "B", "C", "D"). Your task is to find the correct answer (from the given options) for the question from the given article and return one of the options from "A", "B", "C", and "D". Do not generate anything else apart from one of the following characters: "A", "B", "C", "D". There is only one correct answer for each question.
Example: Article: Homework can put you in a bad mood , and that might actually be a good thing. Researchers from the University of Plymouth in England doubted whether mood might affect the way kids learn. To find out the answer, they did two experiments with children. The first experiment tested 30 kids. Someshapes were hidden inside a different, larger picture. The kids had to find the small shapes while sitting in a room with either cheerful or sad music playing in the background. To test their mood, the scientists asked the kids to point to one of five faces, from happy to sad. Children who listened to cheerful music tended to point to the smiley faces while the others pointed to the unhappy ones. The researchers found that sad kids took at least a second less to find the small shapes. They also found an average of three or four more shapes. In the second experiment, 61 children watched one of two scenes from a film. One scene was happy, and the other was sad. Just like in the first experiment, kids who saw the sad scene acted better compared to the others. The researchers guessed that feeling down makes people more likely to focus on a problem or difficult situation. Not all scientists agree with them, however. Other studies argued that maybe, that cheerful music in the first experiment distracted kids from finding shapes. While scientists work on finding out the answers, it still might be wise to choose when to do your tasks according to your mood. After eating a delicious ice cream, for example, write an essay.
Question: Researchers did experiments on kids in order to find out _ .
Options: (A) how they really feel when they are learning (B) whether mood affects their learning ability (C) what methods are easy for kids to learn (D) the relationship between sadness and happiness
Example solution: B
Example explanation: It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment. So, B is the correct answer.

Problem: Article: Experts believe that storms and severe weather in North America and Asia have disrupted bird flight paths across the world and swept huge numbers of bird species towards the British Isles. Birds flying to the other side of the Atlantic or to the Pacific to lay their eggs have been trapped in Britain and Ireland, adding their numbers to native species, and causing great excitement in the bird-watching community. Local birdwatchers have already observed a total of 442 species in the British Isles this year. The highest number ever seen in one year is 445, in 2008. "We only need four more to break our record," said Lee Evans, who runs the British Birding Association. "With three months to go I'm sure we'll do it." Last month an extremely rare Siberian Rubythroat bird was seen in Scotland, sending hundreds of birdwatchers north in the hope of catching a glimpse of this colourful Asian beauty. Another very uncommon bird, the bufflehead duck was cited in Cornwell and caused similar excitement. "I couldn't believe it," said Evans. "The poor thing was completely _ . It must have been blown to England by the storms while trying to fly from Canada to the southern United States for the winter. That's 3000 miles!" Evans said that global warming over the past decade was playing a key role in transforming bird movements across the world. In addition, melting Arctic sea ice may also be opening up bird flight paths over the North Pole, making it easier for birds from the Pacific -- such as the slaty-backed gull and tufted puffin, both of which appeared in London earlier this year -- to reach Britain. Bird-watching is becoming an increasingly popular hobby among all age groups, added Evans. "A fifth of our members are under 18. This is a round-the-year hobby that you can enjoy from the kitchen window or from a car. More and more people are bird-watching, and as a result more and more unexpected species are being spotted in the British Isles."
Question: What is the passage mainly about?
Options: (A) The results of global warming. (B) Changes in the British bird population. (C) Increasing environmental pollution. (D) Worsening British weather.
Solution: B