Answer:
The answer is C. Pollution
Is that a question? If it is not what its the question?
I believe the answer is b) slowly heating the surface
Most radiation exposure comes from natural sources. These so-called "natural sources" include Radon, Internal, Terrestrial, and Cosmic. Among that, Radon proves to be the largest source of radiation. Radon is a naturally occurring radioactive gas that comes from the breakdown of uranium.