Question

the strings and elastic bands of masks and eyewear are considered clean biohazardous contaminated sterile

Explanation:

Masks and eyewear that have been used may come into contact with bodily fluids, pathogens etc. Their strings and elastic bands are likely to be contaminated. They are not clean, biohazardous (which usually refers to more extreme biological risk - posing agents in specific contexts), or sterile.

Answer:

C. contaminated