Judge the following sentence according to the criteria given below: The greenhouse effect gets its ...

Judge the following sentence according to the criteria given below: The greenhouse effect gets its name BECAUSE it keeps Earth's surface and lower atmosphere warm in a way similar to a greenhouse that keeps plants warm enough to grow, regardless of
 
  outside conditions. A) The assertion and the reason are both correct, and the reason is valid.
  B) The assertion and the reason are both correct, but the reason is invalid.
  C) The assertion is correct, but the reason is incorrect.
  D) The assertion is incorrect, but the reason is correct.
  E) Both the assertion and the reason are incorrect.