Which statement describes an example of a positive feedback loop? a. warm-blooded animals sweat when they get too hot. sweating is a method by which the body cools itself. b. a thermostat regulates temperature by turning a furnace or air conditioner on and off. c. when blood flows from a mild cut, blood clots form to prevent excessive bleeding. d. as oceans become warmer they release more co2, which then increases atmospheric and ocean temperatures.