Final answer:
The body responds to cold by reducing blood circulation to the extremities, in order to prevent blood from cooling there and so that the body's core can stay warm.
Step-by-step explanation:
The body responds to cold by reducing blood circulation to the extremities, the hands and feet, in order to prevent blood from cooling there and so that the body's core can stay warm. This is done through vasoconstriction, where the blood vessels in the skin constrict or narrow to conserve body heat. In extreme cases, this can result in frostbite.