A、Since the kindergarten. B、Since the primary school. C、Since the middle school. D、Since the high school. B推断题。根据题干中的the gap可知文中

The Education Select Committee has been examining the underachievement of poor white children in England. Their exam results are much worse than disadvantaged black or Asian pupils.
    The report describes poor white youngsters as "consistently the lowest performing group in the country". The report—Underachievement in Education by White Working Class Children—identifies this as a "real and persistent" problem. Poor white children are already lagging behind when they start primary school, and the gap grows wider as they get older. As each school year passes, this gap sees them falling further behind wealthier white pupils and poor children from ethnic minorities. The rising results among poor black and Asian pupils shows improvements can be made. This report holds a mirror up to the situation—it does not attempt to solve the problem, but it makes some suggestions to lessen this underachievement.
    The report argues that as a particularly low-achieving group, poor white children would have the most to gain from access to outstanding schools and the best teachers. The school need to recruit high-quality teachers who could help these pupils, argues the report. "Schools face a battle for resources and talent, and those serving poor white communities need a better chance of winning," it says. There are practical forms of help, says the report, such as allowing time and space for children to do their homework at school, which could mean extending the school day.
Questions 22 to 25 are based on the passage you have just heard.
22. Whose exam results are much worse than disadvantaged black or Asian pupils?
23. When does the gap appear?
24. What does the rising results among poor black and Asian pupils show?
25. What should the school do to help the poor white children?