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.

Input: Consider Input: Article: In the atmosphere, carbon dioxide acts rather like a one-way mirror or the glass in the roof of a greenhouse which allows the sun's rays to enter but prevents the heat from escaping According to a weather expert's prediction , the atmosphere will be 3degC warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate.If this warming up took place.the ice caps in the poles would begin to inch,thus raising sea level several meters and severely flooding coastal cities.Also.the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere ,possibly resulting in an alteration of the earth's chief food growing zones. In the past,concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet.But the weather experts are now paying more attention to West Antarctic.which may be affected by only a few degrees of warming,in other words,by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels. Satellite pictures show that large areas of Antarctic ice are already disappearing.The evidence available suggests that a warming has taken place.This fits the theory that carbon dioxide warms the earth. However, most of the fuel is burnt in the northern hemisphere,where temperatures seem to be falling.Scientists conclude,therefore ,that up to now natural influences on the weather have gone beyond those caused by man.The question is:Which natural cause has most effect on the weather? One possibility is the variable behavior of the sun.Astronomers at one research station have studied the hot spots and 'cold' spots (that is, the ly less hot spots)on the sun.As the sun rotates ,every 27.5 days,it presents hotter or colder faces to the earth,and different aspects to different parts of the earth.This seems to have a considerable effect on the distribution of the earth atmospheric pressure,and consequently on wind circulation.The sun is also changeable over a long term:its heat output goes up and down in cycles,the latest trend being downward. ' Scientists are now finding shared relations between models of solar weather interactions and the actual climate over many thousands of years,including the last ice Age.The problem is that the models are predicting that the world should be entering a new Ice Age and it is not.One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia of the earth's climate.If this is right, the warming effect of carbon dioxide might thus be serving as a useful opposed balance to the sun's fading heat.
Question: It can be concluded that a concentration of carbon dioxide in the atmosphere would_.
Options: (A) mean a warming-up in the Arctic (B) raise the temperature of the earth's surface (C) prevent the sun's rays from reaching the earth's surface (D) explain the cause of great changes in the climate in the northern hemisphere

Output: B

Input: Consider Input: Article: Every culture has a recognized point when a child becomes an adult, when rules must be followed and tests passed. In China, although teenagers can get their ID cards at 16, many only see themselves as an adult when they are 18. In the US, where everyone drives, the main step to the freedom of adult life is learning to drive. At 16, American teens take their driving test. When they have their license, they drive into the grown-up world. "Nobody wants to ride the cheese bus to school," said Eleanor Fulham, 17. She brought the pressure back to memory, especially from kids from wealthier families. "It's like you're not cool if you don't have a car," she said. According to recent research, 41% of 16 to 19-year-olds in the US own cars, up from 23% in 1985. Although, most of these cars are bought by parents, some teens get part-time jobs to help pay. Not all families can afford cars for their children. In cities with subways and limited parking, some teenagers don't want them. But in rich suburban areas without subways, and where bicycles are more for fun than transportation, it is strange for a teenager not to have a car. But police say 16-year-olds have almost three times more accidents than 18 and 19-year-olds. This has made many parents pause before letting their kids drive. Julie Sussman, of Virginia, decided that her son Chad, 15, will wait until he is 17 to apply for his learner's permit. Chad said he has accepted his parents' decision, although it has caused some teasing from his friends. "They say that I am unlucky," he said, "But I'd rather be alive than driving, and I don't really trust my friends on the road, either." In China, as more families get cars, more 18-year-olds learn to drive. Will this become a big step to becoming an adult?
Question: Which may serve as the BEST title of the article?
Options: (A) Cars Helping You to Grow-Up (B) Driving into the Grown-Up World (C) Teenagers' Driving in America (D) Recognized Point of Becoming an Adult

Output: B

Input: Consider Input: Article: Old-Fashioned Play-For Pay Kids! Come to have a ball! Or 60,000 of them! There's a new type of business franchise that is appearing in shopping malls and neighborhood across America offering pay-per-use indoor playgrounds, which feature toys, games, guided fun and a workout that doesn't break the family bank. As public playgrounds grow increasingly worn and dirty, the for-profit centers offer clean, safe guided activity as well as a variety of challenging exercises to develop kids' physical fitness, usually for a fee of around $ 5 an hour. "Playgrounds are dirty, not guided," says Dick Guggenheimer, owner of the two-month-old Discovery Zone in Yonkers, N. Y., part of Kansas City-based chain, "We are indoors; we are padded; parents can feel their child is safe". In order to satisfy the need of two-earner families, the new franchise stays open in the evenings, long after traditional public playgrounds have grown dark and unusable. However, these new playgrounds are not meant to be day-care centers. Parents are expected to go stay and play with their kids rather than drop them off. But several also provide high-tech baby-sitting services. At some of the Discovery Zones, parents can register their children in special guided programs, then leave them and slip away for a couple of hours to enjoy a movie or dinner. If there is a problem, Mom and Dad are called. The most fun of all, though, is getting to do what parents used to do in the days before two-earner families and two-hour commutes , play with their kids. That, at least, is old-fashioned, even at per-hour rates.
Question: What is this article mainly talking about?
Options: (A) Children can play without parent's care. (B) The fast development of Discovery Zone. (C) A new type of business franchise of kids. (D) The disadvantages of outdoor playgrounds.
Output: C