Radon Gas Is a Naturally Occurring Radioisotope That Is Believed

Radon gas is a naturally occurring radioisotope that is believed to contribute significantly to cancer deaths, even though its primary method of decay is alpha emission. Which of the following is hypothesized to be the cause of this extra sensitivity to the radiation from radon?

A) It is a noble gas and therefore less reactive, lowering its half-life.
B) It is much more highly concentrated in homes than in naturally occurring locations.
C) It is the most common radioactive isotope found in nature and therefore is the most destructive overall.
D) When it decays it leaves trace amounts of other radioactive material in the lungs.
E) None of the above