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 input: 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 output: 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.
Q: Article: Barbara and Barry Zucker - Pinchoff, both doctors from New York City, took their three daughters on a walking safari last year in Tanzania. Barbara told about their experience in Kinbero, "It is the most remote place we have ever been to," camping with a few other Americans, two Tanzanian guides, and several Hadza who had time to sit and chat because they had just killed a giraffe. About 400 members of the Eastern Hadza tribe live in Tanzania today, the only hunter-gatherers who remain in Africa. The Hadza hunt game, gather edible plants and honey, and move from place to place whenever the weather changers. Every two weeks or so, they move to a new campsite. At the Pinchoffs' campsite, three Hadza men stopped by to visit and ended up staying three days. One of the guides gave the men a cigarette. They took out the tobacco, put it in a pipe, and lit the pipe with fire they started. It takes less than two hours for Hadza women to build a new camp. They make huts by bending branches into round structures about six feet high, and then covering them with long, golden grass. If the weather is very wet, the women may choose a dry cave to set up a camp. Some rock caves have been used over thousands of years and are decorated with ancient rock paintings. Whether they sleep in huts, caves or in the open, the Hadza cover themselves only with thin cloths and depend on fire to keep them warm. The Hadza refuse to be "settled" into villages or to have the life of farmers. By 1979, almost all of them had returned to their old ways. They Hadza may be the only tribe in Africa the has never paid taxes.
Question: The passage mainly tells up_.
Options: (A) one of the author's travel experiences (B) the life of the Hadza tribe in Tanzania (C) Barbara's walking safari in Tanzania (D) the efforts of the Hadza to keep their old ways
A:
B