Final answer:
Skin cancer is the most common form of cancer associated with exposure to ionizing radiation, especially UV radiation from the sun. Protective measures such as high-SPF sunscreen can mitigate the risk.
Step-by-step explanation:
The form of cancer most frequently associated with exposure to ionizing radiation is skin cancer. Ionizing radiation, such as ultraviolet (UV) radiation from the sun, causes damage to the DNA within skin cells, leading these cells to grow uncontrollably and form tumors. Prolonged exposure to the sun's UV radiation is the principal cause of skin cancer, which is why protective measures such as wearing sunscreen with a high sun protection factor (SPF), hats, and protective clothing are highly recommended.
Rapidly dividing cells are most susceptible to the damaging effects of ionizing radiation. This makes cancer cells — which divide more rapidly than normal cells — both particularly vulnerable to destruction by radiation therapy and at the same time also more likely to be induced by radiation exposure. It is a notable fact that ionizing radiation can be both a treatment for cancer and a cause of it.