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: Hello-Hello, a creative mobile language learning company, announced the launch of Hello-Hello World, a free application for the iPad that helps people learn a new language by connecting them with native speakers through social networking. The application lets users complete language lessons and connect with Hello-Hello's global community of language learners with members in almost 100 countries to help each other in the learning process. Hello-Hello World is available in 11 different languages and allows users to submit both oral and writing exercises for their friends and Hello-Hello's language experts to review. Users are also able to provide written feedback on their friend's exercises directly from their mobile devices. "The most effective way to learn a new language is through total immersion ,"said Sarah Gontijo, founder and CEO of Hello-Hello. "However, not everyone has the opportunity to live in another country. Hello-Hello World brings the convenience of connecting with native speakers anytime, from anywhere. This can help users not only learn the language but also understand the culture." Hello-Hello World lets users synchronize their information with the Hello-Hello Cloud and then access the content from any mobile device or computer. The application is first being released for the ipad and will become available on a variety of platforms, including the iPhone, Android and Blackberry. The application arrives at a time when tablet computing is driving the creation of new educational tools, such as Hell-Hello World. Many schools and colleges are finding ways to adapt mobile technology for classroom learning. "The market is hot for such pioneering in education and social networking," said Gontijo. "Hell-Hello promises to be the invention that will set the ball rolling and bring innovation to an industry that has seen little change over the years." Technology research firm Gartner predicts that app-store downloads worldwide will double to $17.7 billion as the year closes, and that app-income will hit $15.1 billion, tripling the impact of last year's sales. App-downloads are expected to continue to jump to 185 billion by 2014, at which point worldwide tablet sales are projected to surpass 208 million units.
Question: With the launch of Hello-Hello world, users can _ .
Options: (A) talk to any foreigners in the world (B) speak any foreign languages fluently (C) practice pronouncing words correctly (D) communicate with native speakers anytime
Output:
D