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: For many years, environmental problems have been a major concern to people. Almost all things are related to the word "Green", say, green buildings. A green building means not only the colour of the paint. Also,it refers to environmentally friendly houses,factories and offices. Green building means "reducing the impact of the building on the land", Taryn Holowka of the US Green Building Council in Washington D.C.said. According to Holowka,buildings account for 65 percent of total US electricity use. But green buildings can reduce energy and water use. Also,the buildings are often located near public transportation such as buses and subways,so that people can drive their cars less.That could be good for the environment,because cars use lots of gas and give off pollution. Green buildings are often built on developed land,so that the buildings don't destroy forests. Marty Dettling is the project manager for a building that put these ideas into action.The Solaire has been called the country's first green highrise building. According to Dettling,"We've reduced our energy use by onethird and our water by 50 percent." The Solaire cuts energy in part by using solar power."On the surface of the building we have solar panels which change the sun's energy into electricity,"Dettling explained. The Solaire also has lights that automatically turn off when people leave the room. In addition,the building has lots of windows,allowing people to use the sun for light during the day.The Solaire cuts water by reusing it. Not everyone is eager to move into a green building,however. Some people think that things like solar panels cost more money than more traditional energy source. Anyhow,Holowka said,"It is going to take off."
Question: "A green building"most refers to a(n) _ building according to the passage.
Options: (A) not ripe or modern (B) covering green color1 (C) environmentally friendly (D) fresh or new
A:
C