The main function of the circulatory system is to carry blood away from and towards the heart. Because it is made up of blood vessels, it can move blood throughout the body. Aside from blood, it transports food, water, hormones, enzymes, etc. to or away from the body tissues.
The circulatory system aid to warm or cool the body when it is transporting blood. The blood vessels will dilate in this process thereby discharging the heat coming the blood outside of the body. The blood vessels will constrict so that the heat is kept.
The circulatory system helps support the immune system by transporting the immune cells.
The circulatory system does not act as a heater.
Answer - Option 2 - Transport system