单项选择题
Questions 20 to 22 are based on the conversation you have just heard.
A．A lot of good publicity. B．Talented artists to work for it. C．Long-term investments. D．A decrease in production costs.
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.