I began to send e-mails when I was 17. I discovered Google 5 years later. Now, I use the internet all the time. The Internet has become so popular that 90 percent of 12-to-17-year-olds in the United States use the internet, and about half of these kids use it every day. They visit chat rooms and send e-mails. They go to websites to get information for their homework.
"Kids are now living in a virtual(虚拟的) world," says Greenfield, an expert at University of California, "As the Internet is becoming more and more important for our life, we should worry about one question: Is the Internet good or bad for kids? "
"It's ***to answer the question because the Internet involves(涉及) so many things," says Justine, who is from Northwestern University. "They include online computer games, news, messages and even e-mails to your grandmother." So more and more people believe that the online world can be helpful in some ways but dangerous in others.
“Although it's not easy to tell whether it's good or bad,”says Justine, "the Internet, at least, is very useful and can be  used widely by everyone in the world.
The writer discovered Google at the age of         .

A．5

B．12

C．17

D．22

Greenfield         .

A．is an expert from Northwestern University

B．wants to stop all the kids from using the Internet

C．is worrying about whether the Internet is good or bad for kids

D．thinks that the Internet is good for all the kids in the world

in the passage should be the word “       “.

A．difficult	B．possible
C．easy	D．Good