Which of the following can cause cancer as well as cure it depending upon its intensity and use?

Correct answer: (c) Ionized radiation

Explanation

Ionizing radiation (X-rays, gamma rays, alpha/beta particles) can both cause cancer by damaging DNA and cure cancer through controlled radiotherapy.

The effect depends on its intensity, dose and use – low uncontrolled exposure harms cells, while targeted high doses destroy tumour cells.

Tobacco and alcohol only cause cancer, and ultraviolet rays mainly cause skin cancer, none cure it.