Given the task definition, example input & output, solve the new input case.
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
Output: B
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.

New input case for you: Article: One important attraction of walking is its long-lasting appeal. Whereas jogging and aerobic dancing can _ quickly, walking provides a popular activity that seems to endure. Fitness foundations estimate that 35 million adult Americans walk for exercise every day, with at least 15 million walking two or three times a week. Among the most regular walkers are those 65 years and older--evidence that walking is an exercise that lasts. In addition to its many physical benefits, walking, like other physical activities, has a comforting effect on the psyche. Walking can help you to think more clearly and feel more relaxed. It also can be a sociable activity. An early morning walk around the neighborhood provides an opportunity to chat with friends or simply admire the flowers. Or because it does not require a team or even a partner, walking is something you can do on your own time, by yourself, whenever the mood strikes. Easily affordable, all you need to start walking is enthusiasm and a pair of comfortable and sturdy low-heeled shoes. Dr.ChristineL. Wells recommends an Oxford-style shoe with ties for better foot support; she does not recommend sneakers or other "cheapies". If you plan to walk regularly, you might want to invest in a pair of so-called walking shoes. If so, expect to spend at least $35. For walking during the hotter months, early morning or evening hours are best. Clothes should fit loosely and be lightweight and light-colored. Elderly walkers should consider wearing long sleeves, and all Arizonans need to be particularly concerned about skin cancer. Dr. Wells suggests wearing sunscreen as well as a side-brimmed hat to protect your eyes, ears, nose and back of the neck. Walkers also should drink an adequate amount of water. Wells advises drinking an 8-ounce glass of water before you start out, and more when you return. "If you walk four miles or more a day in Arizona, I also recommend that you carry a water bottle," she says. " And water is just fine; you don't need those fluid-replacement or electrolyte drinks."
Question: Which of the following is NOT mentioned as a benefit of walking?
Options: (A) It improves one's appetite. (B) It's an inexpensive exercise (C) It helps to comfort the mind. (D) it can be an individual or social activity
Output:
A