In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Input: Consider Input: Article: Today, traditional opinions about men still exist. A man has to be strong, brave, sports loving and manly. Anything less would not be considered manly. Sports such as football, basketball and boxing all tend to be men's sports. However, the dance of ballet is considered _ because it requires nice movements. This tradition is shown in the movie, Billy Elliot. Billy Elliot is a movie that protests against this traditional view of men. Billy Elliot is an eleven-year-old boy that has a natural talent for ballet dancing, but his father will not allow it. Billy's father wants him to take up boxing and become stronger, but Billy goes against his father's wishes and takes up ballet dancing. This difference of opinion makes Billy sad. What's more, his friends also laugh at him. After saving enough money, his father sends Billy to a weekly boxing course; however, Billy doesn't enjoy boxing because he always loses in matches and is often hurt. His ballet teacher, Mrs. Wilkinson thinks that men or women should not be judged by the activities they like to do, so she tells Billy's father that although he wants his son to make a good living, he should let his son do what he loves to do because he has a talent for it. When his father finally realizes the truth, Billy is surprised. In the end, with the help of his father, brother and all the people around him, Billy goes to the Royal Ballet Academy in London and becomes a very successful ballet dancer.
Answer: He loves ballet.

Output: Why is Billy laughed at by other children?

Input: Consider Input: Article: Polar bears are born in dens on land and their mother stays with them for the whole winter without eating anything. The mother and the babies come out from the dens around March, _ from a long winter and must immediately go hunting to find food to stay alive. Now, the only hunting they know is to catch seals from floating ice in the open ocean. In March, polar bear mothers and babies have to swim from the land in Spitsbergen to the edge of the polar ice cap. Normally this is a short swim, since in March the polar ice cap is very close to the land, and the polar bears, and even the babies, are good swimmers. However, last year we saw that the polar ice cap had become smaller in size due to global warming. Swimming hundreds of miles, especially when they are hungry and have babies following them, is really hard, and many bears are dying because of starvation. The polar bear population in the Spitsbergen area was once threatened by hunters. In the 1970s, a ban on hunting was imposed and the polar bear population has been steadily increasing from just a few hundred to about 2,000 to 3,000. This was a great success story. However, now, because of global warming, the population is again in danger. If we do not stop making so much carbon dioxide, we will lose these beautiful animals forever. The polar bears are just one example of animals that have become endangered because of man's appetite for energy obtained by burning fossil fuels. All life on earth could be in danger unless we change our ways. What can we do? To reduce the amount of carbon dioxide in the air we must save and make energy without burning coal and oil. Instead, we can use the sun or the wind to generate electricity. We must also cut down on needless driving and turn off things that use electricity when we are not using them. In addition, we have to stop cutting down forests and start planting more trees.
Answer: To catch seals for food.

Output: Why do the bears swim to the edge of the polar ice cap?

Input: Consider Input: Article: Motherhood may make women smarter and may help prevent dementia in old age by bathing the brain in protective hormones , U.S.researchers reported on Thursday. Tests on rats show that those who raise two or more litters of pups do considerably better in tests of memory and skills than rats who have no babies, and their brains show changes that suggest they may be protected against diseases such as Alzheimer's .University of Richmond psychology professor Craig Kinsley believes his findings will translate into humans."Our research shows that the hormones of pregnancy are protecting the brain, including estrogen , which we know has many neuroprotective effects," Kinsley said. "It's rat data but humans are mammals just like these animals are mammals," he added in a telephone interview."They go through pregnancy and hormonal changes." Kinsley said he hoped public health officials and researchers will look to see if having had children protects a woman from Alzheimer's and other forms of age-related brain decline. "When people think about pregnancy, they think about what happens to babies and the mother from the neck down," said Kinsley, who presented his findings to the annual meeting of the Society of Neuroscience in Orlando, Florida. "They do not realize that hormones are washing on the brain.If you look at female animals that have never gone through pregnancy, they act differently toward young.But if she goes through pregnancy, she will sacrifice her life for her infant--that is a great change in her behavior that showed in genetic alterations to the brain."
Answer: They know it through their own experience.
Output: How do scientists know "Motherhood may make women smarter"?