单选题 In the Xuzhou survey ,how many children have extra private lessons?

【正确答案】 B
【答案解析】[解析] 由文章第八段第二句A survey of 250 students in Xuzhou found that 10% of their parents hired tutors可知，徐州做的一份调查表明，10%的父母为孩子请家教。因此250名学生中也就有25个孩子补课。