In the eyes of the author, conventional opinion on conflict is ________.

A．most Americans are reluctant to switch to public transportation systems
B．the present level of oil prices is considered unacceptable
C．other countries will protest its increasing greenhouse emissions
D．it should take a lead in conserving natural resources

A．The use of fuels other than gasoline.
B．Improved energy efficiency.
C．The introduction of less polluting driving systems.
D．Reducing car use by carpooling.