Final answer:
Radiation, including ionizing radiation like X-rays and gamma rays, leads to the destruction of DNA by causing breaks in the DNA strands and modifying DNA bases. The correct option is A.
Step-by-step explanation:
The method that causes destruction of DNA is Radiation. Ionizing radiation, which includes forms such as X-rays and gamma rays, can cause single- and double-stranded breaks in the DNA backbone. These breaks are caused through the formation of hydroxyl radicals upon radiation exposure.
Additionally, ionizing radiation can lead to modifications of DNA bases, such as the deamination of cytosine to uracil. Nonionizing radiation, like ultraviolet light, can also damage DNA by inducing mutations, although it is typically used for surface sterilization as it does not penetrate deeply.
Radiation exposure is a potent means of microbial control because it can nonspecifically damage DNA, proteins, and other cellular components, therefore being used to sterilize medical devices and certain foods. The correct option is A.