单选题 Studies investigating fathers' involvement in child-rearing show that

A、 this improves kids' mathematical and verbal abilities.
B、 the more time spent with kids, the better they speak.
C、 the more strict the fathers are, the cleverer the kids.
D、 girls usually do better than boys academically.

【正确答案】 A

【答案解析】[解析]由文章第七段第一句可知A正确。故应选A。