题目内容：

Putting more green space around an elementary school may help students develop some mental abilities, a study suggests.

Researchers tested students repeatedly over the course of a year on attentiveness and working memory, which is the ability to keep something in mind temporarily for performing a task. The study tracked more than 2,000 students in 36 primary schools in Barcelona, Spain. The pupils were in the second to fourth grade when the study began. Overall, students whose schools are surrounded by more green space improve more pupils from schools with less green space.

“Policy makers should know that more green space around the school is better for cognitive (认知的) development and that they should make sure that kids can see and play in green areas,” one author, Mark Nieuwenhuijsen of the Center for Research in Environmental Epidemiology in Barcelona, said in an email. “Existing urban schools should think about replacing concrete or other hard surfaces with green space, and even a few trees may help,” he suggested.

The researchers used satellite images to group schools according to how much green space appeared on the school ground and within about 55 yards of the school’s surrounding property. Their analysis indicated that differences in socioeconomic factors between schools did not account for the study outcome.

Sally Augustin, a psychologist in La Grange Park, Illinois, who used research on how people react to their surroundings to consult on design of buildings, products and services, said the results make sense to her. Augustin, who did not participate in the new study, said the results fit with previous findings that views of nature help children and adults lower stress and perform mental tasks better.

1.What do we know about the findings of the study?

A. Attentiveness (专注) is the most important quality for students.

B. A good memory enables students to perform a task better.

C. More green space may help the mental development of students.

D. Schools surrounded by more green space are favored by parents.

2.According to Mark Nieuwenhuijsen, policy makers should _______.

A. reduce the noise near the school

B. reduce air pollution from vehicles

C. provide more green space for kids

D. encourage kids to play more sports

3.How are the schools classified by the researchers?

A. By green space.    B. By test scores.

C. By size.    D. By position.

4.Why is Augustin mentioned in the passage?

A. To introduce another interesting study.

B. To make the findings of the study more convincing.

C. To present new evidence for the study.

D. To show a different viewpoint.