Final answer:
When an instrument will only come into contact with the skin of a patient, it is considered a noncritical item. Disinfecting these items with a low-level germicide is sufficient to reduce the number of microbes on the instrument's surface and prevent infection.
Step-by-step explanation:
The correct answer is D) low-level germicide.
When an instrument will only come into contact with the skin of a patient, it is considered a noncritical item. Noncritical items are those that only touch intact skin and do not penetrate sterile tissues or come into contact with mucous membranes. Disinfecting these items with a low-level germicide is sufficient to reduce the number of microbes on the instrument's surface and prevent infection.