Irradiating food can be used to kill existing microorganisms in the food, and irradiation causes chemical changes. Given these facts, what can be used to kill existing microorganisms in food among the following options:
- chemical changes
 - Dehydration
 - deoxyribonucleic acid
 - bacteria
 - an electron microscope
 - hydration
 - electromagnetic energy
 - single-celled organisms


 

 chemical changes        