单项选择题
Passage One Questions 27 to 30 are based on the conversation you have just heard.
A．It has not been very successful. B．It has long become a new trend. C．It has met with strong resistance. D．It has attracted a lot of users.
A．Half of the methane in the atmosphere is from animals. B．Methane has become the chief source of greenhouse gas. C．Consumer behavior may be influenced by the environment. D．Meat consumption has an adverse effect on the environment.
A．They do not know any solution. B．They do not give up drunk driving. C．They do not behave in public places. D．They do not admit being alcohol addicts.