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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.

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
Solution: Researchers did experiments on kids in order to find out _ .
Why? It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

New input: Article: Fumbling with the buttons to find a good song while driving has been linked to increased risk of crashes, but is listening to music risky? "It depends on the music," says a report published in the October issue of Accident Analysis & Prevention. The study found teenage drivers who played their own music had significantly more traffic violations compared with background music designed by the researchers to minimize driving distractions, or no music. Researchers at Ben-Gurion University in Israel recruited 85 drivers about 18 years old; just over half were male. The _ were each assigned to drive six challenging road trips that were about 40 minutes long, accompanied by an experienced driving instructor. Music was played on four trips, two with selections from the drivers' playlists, mostly fast-paced vocals, and two with background music, which was a mixture of easy listening, soft rock and light jazz designed to increase driver safety. No music was played on two trips. Subjects rated their mood after each trip and in-car data recorders analyzed driver behavior and errors. All 85 subjects committed at least three errors in one or more of the six trips; 27 received a warning and 17 required steering or braking by an instructor to prevent an accident. When the music was their own, 98% made errors; without the music, 92% made errors; and while listening to the safe-driving music, 77% made errors. Speeding, following too close, inappropriate lane use, one-handed driving and were the common violations. The male subjects were more aggressive drivers and made more serious errors than female subjects. The teens played their own music at a very loud volume but significantly decreased the sound level when listening to the safe-driving music, researchers said. Mood ratings were highest on trips with driver-preferred music.
Answer: increase drivers' safety
Solution:
In the research, soft rock and light jazz are likely to _ .