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阅读材料，回答题：Do bring about greater competition
About eight million school-age children are home alone after school. These are the hourswhen the number of violent crimes peaks and when youths are most likely to experiment with alco-hol, tobacco, and drugs. Many older children take care of themselves after school for an hour or twountil aparent comes home, and research suggests that some of these children are more at risk ofpoor grades and risky behaviors.
Studies have been done to find out what helps to reduce these kinds of risky behaviors amongyouths. One study of Chicago neighborhoods showed that after-school programs resulted in less vio-lence even in poor neighB．orhoods.
After-school programs can help to reduce crime and violence because they offer activities tochildren and youths during their out-of-school time. In addition to helping youths make use of af-ter-school hours, after-school programs provide teens with opportunities to develop caring relation-ships with adults. Studies have found that high-quality relationships with parents and other adults,as well as good use of time, are very important for healthy development in youth.
After-school programs can also be used for teens who hang out at friends' houses and playb．asketd．all when a parent or other responsible adult is at home. The programs can also be helpfulfor formal after-school activities, including" drop-in" programs that are provided B．y organizations.Despite the benefits of after-school programs, there are many reasons why some parents do notuse them. Programs may be too expensive, of poor quality, or hard to join. Some older children andyoung teens may refuse to attend programs that seem like they are just child care. Parents may feeluncertain about how much freedom is proper for children and youths who are beyond the tradition-al child care years. However, research supports the effectiveness of these programs in protectingmiddle school and high school youths from risk and harm.
Which of the following is abenefit of after-school programs? A．They help to avoid crime and violence during that time.
B．They help youths do things on their own during after-school hours.
C．They help teens develop caring relationships with classmates.
D．They help to reduce risky behaviors among youths.
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