题目内容：

Spring soccer season is under way,and many youth leagues are playing under new safety rules.In November,the US Soccer Federation said that players on its teams who are 10 or younger are no longer allowed to head the ball. Players ages 11 to 13 have limits on how often they can practice heading.The new rules are made to prevent kids from getting concussions（脑震荡）—injuries caused by a blow to the head that shakes the brain.Common problems include headaches and dizziness.Severe concussions can lead to long brain damage.

Heading the ball can be one of the riskiest parts of soccer.Sometimes the force of hitting the ball with their heads gives players concussions.But more often,players receive concussions when they accidentally knock heads with other players and hit their heads on the grass."More concussions happen during the act of heading than any other action in soccer,"explains Dr.Robert Cantu,an expert on brain injuries.

So far,the new rules are made only to teams that are part of the US Soccer Federation.But the group says it hopes other leagues will soon follow its example.

Former US soccer star Brandi Chastain is one of the leaders of the activity to ban heading in Youth soccer.She applauds the rule change.Last month,Chastain showed her determination of learning more about the effects of heading when she promised to donate her brain to science after she dies.

"If there's any information to be gathered on the study of someone like me,who has played soccer for 40 years,it feels like my responsibility,"Chastain told The New York Times.

1.What can we learn from the first two paragraphs?

A. Players needn't take the risk of heading the ball in soccer.

B. All of the players' headaches result from hitting heads on the grass.

C. The act of heading can cause more concussions than other actions in soccer.

D. Players must receive concussions when knocking heads with other players.

2.What is Brandi Chastain's attitude towards the new safety rules in playing soccer?

A. Unconcerned.    B. Positive.

C. Negative.    D. Doubtful.

3.From the text,we can learn     .

A. Brandi Chastain suffers from very severe concussions

B. concussions caused by heading the ball can not be healed

C. Brandi Chastain is willing to devote herself to the safety of soccer players

D. the new rules in soccer have been carried out among all of the American leagues