阅读下列短文，从每题所给的A、B、C、D四个选项中，选出最佳选项。

D

Parents who help their children with homework may actually be bringing down their school grades. Other forms of prenatal involvement, including volunteering at school and observing a child's class, also fail to help, according to the most recent study on the topic.

The findings challenge a key principle of modern parenting(养育子女) where schools except them to act as partners in their children's education. Previous generations concentrated on getting children to school on time, fed, dressed and ready to learn.

Kaith Robinson, the author of the study, said, "I really don't know if the public is ready for this but there are some ways parents can be involved in their kids' education that leads to declines in their academic performance. One of the things that was consistently negative was parents' help with homework." Robinson suggested that may be because parents themselves struggle to understand the task." They may either not remember the material their kids are studying now, or in some cases never learnt it themselves, but they're still offering advice."

Robinson assessed parental involvement performance and found one of the most damaging things a parent could do was to punish their children for poor marks. In general, about 20% of parental involvement was positive, about 45% negative and the rest statistically insignificant.

Common sense suggests it was a good thing for parents to get involved because "children with good academic success do have involved parents ", admitted Robinson. But he argued that this did not prove parental involvement was the root cause of that success." A big surprise was that Asian-American parents whose kids are doing so well in school hardly involved. They took a more reasonable approach, conveying to their children how success at school could improve their lives."