Question

hair and some intermediate filaments are composed of proteoglycans. collagen. keratin. microtubules. microfilaments.

Explanation:

Hair and some intermediate filaments are made of keratin. Keratin is a fibrous structural protein. Proteoglycans are related to the extracellular - matrix and not the main component of hair. Collagen is a major component of connective tissues. Microtubules and microfilaments are parts of the cytoskeleton and not the composition of hair and intermediate filaments in question.

Answer:

C. keratin