The right answer is c.
Our body is made up of about thirty thousand billion cells. Each of these cells contains hundreds of mitochondria that use the nutrients to produce the energy needed to perform all of our bodily functions. Some of this energy is dissipated as heat.
* If this energy is not enough because the outside temperature is very low, we shiver, because our muscles start to tremble. This friction of the muscles generates heat. In addition, brown adipose tissue can elevate TC by using as heat most of the energy produced by mitochondria. If the outside temperature is winter, the blood vessels in the skin contract to reduce heat loss on the body surface.
* If the TC is too high, we can dissipate heat through perspiration (evaporation of water on the surface of the body has a cooling effect) and by the exhalation of hot air.