A、They might have watched a lot of TV. B、They must be uninterested in math. C、They may be unable to go to college. D、They might

Too much TV-watching can harm children’s ability to learn and even reduce their chances of getting a college degree, new studies suggest in the latest effort to examine the effects of television on children.
    One of the studies looked at nearly 400 northern California third-graders. Those with TVs in their bedrooms scored about eight points lower on math and language arts tests than children without bedroom TVs.
    A second study, looking at nearly 1,000 grown-ups in New Zealand, found lower education levels among 26-year-olds who had watched lots of TV during childhood. But the results don’t prove that TV is the cause and don’t rule out that already poorly motivated youngsters may watch lots of TV.
    The study measured the TV habits of 26-year-olds between ages 5 and 15. These with college degrees had watched an average of less than two hours of TV per week night during childhood, compared with an average of more than 2.5 hours for those who had no education beyond high school.
    In the California study, children with TVs in their rooms but no computer at home scored the lowest while those with no bedroom TV but who had home computers scored the highest.
    While this study does not prove that bedroom TV sets caused the lower scores, it adds to accumulating findings that children shouldn’t have TVs in their bedrooms.
Questions 30 to 32 are based on the passage you have just heard.
30. What do we learn about the low-scoring group according to the California study?
31. What is the researchers’ understanding of the New Zealand study results?
32. What can we learn from the end of the passage?