Question

to supply hair with nutrients
to produce sweat
to contract and raise hair upright
to perceive touch around the hair bulb
what is the function of the arrector pill muscle?

Explanation:

The arrector pili muscle is a small muscle attached to hair follicles. When it contracts, it causes the hair to stand upright. This is a physiological response often associated with cold or emotional states (like fear). Among the given options, "To contract and raise hair upright" directly describes this function.

Answer:

To contract and raise hair upright