阅读下列短文，从每题所给的四个选项中选出最佳答案。

　　How to protect children Web fans from unsuitable material on-line while encouraging them to use the Internet has long been discussed in US.

　　For some parents the Internet can seem like a jungle, filled with danger for their children. But jungles contain wonders as well as hazards and, with good guides, some education and a few precautions (预防措施), the wilds of the Internet can be safely navigated (航行). “Kids have to be on-line. If we tell our kids they can't have access (进入) to the Internet we're cutting them off from their future,” said an expert.

　　Most kids have started to learn to use search engines. Many of them are great for finding tons of interesting Internet sites, and they can also locate places where you might not want your kids to go. There are search engines designed just for kids. A certain software contains only sites that have been selected as safe. But the most popular that was to limit access would be to use what is known as a “content screener (过滤) ”. But this can't be wholly reliable, and the best thing parents can do is to talk to their kids and let them know what's OK or not OK to see or do on the Internet. Another way is that mum or dad is nearby when the child is surfing (浏览)the Internet.

　　A few other tips：

　　 Don't put the PC in a child's room but keep it in an area where mum or dad can keep an eye on things. That also makes the Internet more of a family activity.

　　 Ask your child what he or she has been doing and about any friends they make on-line.

　　 Tell your child not to give on-line strangers personal information, especially details like address and phone number.

　　 And tell your children never to talk to anyone they meet on-line over the phone, send them anything, accept anything from them or agree to meet with them unless you go along.

1．The passage is mainly about the subject of ________.

[　　]

A．American children's going on-line

B．Internet in America

C．appreciating Internet

D．opposing Internet

2．The best way to protect children from improper materials is ________.

[　　]

A．to install a content screener in the computer

B．to buy some search engines for the children

C．to be nearby when they are surfing the Internet

D．to talk to the children and persuade them to tell right from wrong

3．Which of the following is right according to the passage?

[　　]

A．Surfing the Internet is the best method of educating children.

B．Children's not having access to Internet may have effect on their progress.

C．Using a content screener is most reliable for keeping children having access to Internet.

D．Search engines can help children to select materials fit for them.

4．The passage tells most about ________.

[　　]

5．According to the passage, we can infer that ________.

[　　]

A．softwares fit for children want programming

B．a child who is on-line is in danger

C．Internet is a jungle full of danger

D．Internet contains lots of harmful sites