The correct option is C Heat is lost
During vasodilation, the blood vessels near the skin surface and increase in diameter. This allows more blood flow near the skin surface. Higher blood flow near the skin surface allows more heat from the body to escape. This happens during hot weather.
In cold weather, vasoconstriction happens where the diameter of blood vessels near the skin decreases. This decreases the blood flow near the skin surface, minimising heat loss and increasing the temperature of the body.