What is one of the ways in which the skin cools the body?
creating extra keratin
decreasing the body's melanin
sending more collagen to the cells
dilating surface blood vessels

D) dilating sureface blood vessels

When you're out in cold weather, your skin triggers shivering so the blood vessels will contract and keep you as warm as possible. But if there's a heat wave, you'll sweat to increase the blood flow to the capillaries, which in turn increases sweating. This process cools you off as the water evaporates from your skin.

C- a hypothesis or d- an observation