On countless mornings over the past year, I stood with my son, James, in our driveway, watching our neighbor hurry off to kindergarten．My wife and I wanted to give James the best  education, but that meant we'd have to change our jobs and spend less time with our kid．I asked myself, "Would this trade-off be worth it?" When I look at the research on child development, I think it might not．Where our kids go to school might matter less than most American parents think．
Social scientists have long tried to determine why some children grow up to be successful．In a 2001 study, Greg Duncan, a professor of education at the University of California, measured the influence that the people in a child's life have on how well the child does in school．Duncan and his team found almost no relationship between how students did on the test and whom they sat beside in class, whom they hung out with after school and who lived in their block．The only meaningful link they found was between siblings （兄弟姐妹） and twins in particular．
For a long time, scholars thought that a family's income heavily affected how well kids did   in life．But that might not be the case．When Susan Mayer at the University of Chicago looked at the relationship between family income and lifetime achievement, she ran a series of experiments to measure it, finding such outcomes weren't caused by income．She argued that the things that make a difference are relatively inexpensive: the number of books a kid has or how often his family goes to museums．
Lareau, another scholar began one of the most in-depth observations of American parenting．He concluded that success is much more related to the amount of time parents spend with their children．He said "Many parents I interviewed are anxious about their children's futures．But they have exaggerated（夸大） the sense of the risks involved if they don't give their children 'the best' of everything．"
So at last, we decided to leave things as it were．More time with our kid is the best we can provide．
The first paragraph is intended to _．

A．introduce the topic of the passage

B．confirm the result of a research

C．stress the importance of good education

D．support a research on child development

From the passage we know that most American parents _．

A．spend a lot of time with their children

B．like to buy a variety of books for their children

C．think children's achievement largely depends on schools

D．believe their income cannot afford children's education

Who believes children's brothers and sisters may influence their academic performance?

A．Lareau．

B．Greg Duncan．

C．Susan Mayer．

D．James．

Which of the following can be the best title of the passage?

A．Parents' time matters to children's future．

B．School education determines children's future．

C．Family income counts to children's achievements．

D．Less education means more risks for children's success．