Final answer:
Oil and grease can interfere with the proper functioning of oxygen components by coating their surfaces and preventing oxygen molecules from interacting with other substances.
Step-by-step explanation:
Oxygen components need to be kept free of oil and grease because these substances can interfere with the proper functioning of oxygen. Oil and grease can coat the surfaces of oxygen components and prevent oxygen molecules from interacting with other substances.
This can limit the effectiveness of oxygen in processes such as combustion, respiration, and chemical reactions.