In a recent survey of 3,000 Chinese teenagers, more than three-fourths identified the Internet as their most important source of information on sex. Books and friends followed, with school and parents ranked as the least important resources. Even so, 71 percent said the web's obscene content is disturbing for teens. The chief of the Institute for Research on Sexuality and Gender at Renmin University of China said sex education should be compulsory. "We should not focus on what we can tell teenagers," said Pan Suiming. "We should focus on what they want to know." "There is a severe lack of formal sex education in China, so many teenagers turn to the Internet," said Ye Qing, a post-graduate student at the Second Military Medical University who operates an online sex education site for youths. The China Youth Daily newspaper conducted the poll.