The correct option is A UV rays
Non-ionizing radiations are the ones that have sufficient energy to move around atoms in a molecule or to make them vibrate, but not enough to remove electrons. On the other hand, ionizing radiations carry enough energy to remove the tightly bound electrons from atoms which in turn creates ions. X-rays, γ-rays and β-rays are the ionizing radiations with the lower wavelength that penetrate deep in the target. UV rays are non-ionizing radiations with higher wavelength and lower penetrance that disturb the hydrogen bonds by introducing thymine dimer in DNA chains. The correct answer is A.