Concept:Food preservation in industry uses ionising radiation to kill harmful microorganisms.
Explanation:Gamma rays have strong penetrating power and can destroy bacteria, moulds, and insects in food.
This technique is called food irradiation.
It is used commercially to extend the shelf life of food.
The food does not become radioactive after the process.
Carbon dating, nuclear fission, and nuclear fusion are not used for food preservation.
Answer:B. Irradiation of gamma rays