Which of the Following Best Explains the Effect of Greenhouse

Which of the following best explains the effect of greenhouse gases on Earth's atmosphere?

A) absorb some of the energy Earth radiates out into space.
B) produce more carbon dioxide which generates more plant growth.
C) absorb some of the incoming radiation from the Sun.
D) act as a shield that reflects some of the incoming radiation from the Sun.
E) allow the atmosphere to hold more water vapor.