One Way in Which the Ionizing Radiation Occurring Naturally in the Environment

Multiple Choice

One way in which the ionizing radiation occurring naturally in the environment has been beneficial to the human race is

A) in the operation of the electron microscope.
B) in making nuclear fission possible.
C) in producing the mutations that are essential for the process of evolution.
D) the application of solar radiation to the treatment of cancer.
E) nonsense-- there are no beneficial uses of naturally- occurring high- energy radiation.