Which sentence describes an example of a positive feedback loop? a: warm blooded animals were when they get too hot. sweating as a method by which the body close 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 get hotter, they release more co2, which then increases atmospheric and ocean temperatures.