Correct Answer: Blood capillaries

Solution : The correct option is blood capillaries.

Among the structures present in mammalian skin, blood capillaries play a significant role in helping to regulate body temperature. Blood capillaries in mammalian skin help regulate body temperature by constricting to conserve heat in cold conditions and dilating to dissipate excess heat in warm conditions. By regulating blood flow to the skin's surface, blood capillaries in the skin help maintain the body's core temperature within a narrow and optimal range.