2 - What are the primary sources of ionizing radiation? Give examples of each

Ionizing radiation comes from these main sources:

Nuclear reactions in the Earth's sun and stars in space.

Radioactive decay in the body's tissues and in the soil.

Radioactive decay of unstable elements in rocks, especially rocks that contain radium and release radon gas.

Other examples of ionizing radiation include alpha, beta, and gamma rays from radioactive decay.