30．Stressful environments lead to unhealthy behaviors such as poor eating habits, which _________ increase the risk of heart disease.

　　　 A. by chance　　　　　　　　　 B. in return　　　　　　　　 C. in turn　　　 　　　　　　　　　　　　　　 D. in a row

29．Hundreds of thousands of soccer fans are likely to get their first taste of live 3D viewing during this year's World Cup, the vast majority of them in cinemas　　 at home, according to football body FIFA.

A. more than　　　　　　　　　 B. rather than　　　　　　　　　 C. other than　　　　　　　　　　　　　 D. less than

28．Every child is __________, with their own needs, preferences and talents.

A. productive　　　　　　　　　 B. familiar　　　　　　　　　 C. original　　　　　　　　　　　　 D. unique

27．In the Gulf of Mexico the animals' presence close to shore means their usual habitat is badly polluted, and the crowding could ________ mass die-offs as fish run out of oxygen.

A. result from　　　　　　　　　　 B. benefit from　　　　　 C. devote to　　　　　　　　　　　　　 D. result in