单项选择题A．To stop using fossil fuels.B．To reduce carbon dioxide emissions.C．To move to colder places.D．None of the above.

单项选择题A．It’’s cold and warm air is needed.B．It’’s cool enough, but an open window could make it too cold.C．It’’s hot outside, so don’’t open the window.D．It’’s nice and warm in the room.