In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Let me give you an example: Article: Homework can put you in a badmood , 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.
Answer: whether mood affects their learning ability
The answer to this example can be: Researchers did experiments on kids in order to find out _ .
Here is why: It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

OK. solve this:
Article: Scientific experiments can sometimes go wrong and when they do the results may range from the disastrous to the troubling. One such experiment took place in South America about fifty years ago. Whether its final consequences will cause serious damage or nothing more than a small trouble still remains to be seen. The story began in 1956 when an American scientist working in Brazil decided to solve the problem of increasing the productivity of that country's bees. He imported a very active type of African bee from Tanzania and mated it with the more easy-going native variety to produce a new kind of bees. The new bees worked harder and produced twice as much honey. It seemed that Professor Kerr, for that was the scientist's name, had a total success on his hands.www.zxxk.com Then things began to go wrong. For some reason as yet unseen, but perhaps as a result of something in their environment, the new bees began to develop extremely attacking personalities. They became bad-tempered and easy to be angry, attacked the native bees and drove them from their living places. But worse was to follow. Having taken over the countryside, the new bees, with their dangerous stings , began to attack its neighbors -- cats, dogs, horses, chickens and finally man himself. A long period of terror began that has so far killed a great number of animals and about 150 human beings. This would have been bad enough if the bees had stayed in Brazil. But now they are on the move, heading northwards in countless millions towards Central and North America, and moving at the alarming speed of 200 miles a year. The countries that lie in their path are naturally worried because it looks as if nothing can be done to stop them.
Answer: are not yet certain
Answer:
The results of the South American experiment _ .