According to the CDC, Critical Instruments Are Those That

According to the CDC, critical instruments are those that:

A) penetrate soft tissue, contact bone, enter into or contact the bloodstream or other normally sterile tissue.
B) contact mucous membranes but do not penetrate soft tissue, contact bone, enter into or contact the bloodstream or other normally sterile tissue.
C) contact the skin.
D) are very expensive and in short supply.