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: China is known as a state of manners and ceremony . Many proverbs have been passed down from generation to generation such as "Polite behavior costs nothing" or "Showing respect demands reciprocity " and so on. For instance, there is an interesting short story. Once upon a time, a man went on a long tour to visit his friend with a swan as a gift. But it escaped from the cage on the way. Though he tried hard, he got hold of nothing but a feather . Instead of returning home, he continued his journey with the swan feather. When his friend received this unexpected gift, he was deeply moved. And the saying "The gift is nothing much, but it's the thought that counts." was spread far and wide. Chinese used to cup one hand in the other before the chest as a greeting. This tradition has a history of more than 2, 000 years and nowadays it is seldom used except in the Spring Festival. And shaking hands is more popular on some formal occasions. Bowing, as to show respect to the higher level, is often used by the lower like subordinates , students, and attendants . But at present Chinese youngsters prefer to simply nod as a greeting. In a way, this development shows the ever-increasing pace of modern life. It is common social practice to introduce the junior to the senior, or the familiar to the unfamiliar. When you start a talk with a stranger, the topics such as weather, food, or hobbies may be good choices to break the ice. For a man, a chat about current affairs , sports, stock market or his job can usually go on smoothly. Similar to Western customs, you should be careful to ask a woman private questions. However, relaxing talks about her job or family life will never put you into danger. She is usually glad to offer you some advice on how to cook Chinese food or get used to local life. Things will be quite different when you've gotten to know them. Though Chinese are said to be implicit , they are actually humorous enough to be pleased about the jokes of Americans.
Question: The passage is mainly about _ .
Options: (A) Chinese proverbs (B) Chinese humour (C) Chinese manners (D) Chinese languages
Output:
C