Single Answer $(10$pt$)$: Schematically, a Carnot refrigerator operates between two reservoirs at TH and TC$.$ Which of the following statements is true about the operation of the Carnot refrigerator?$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ A$)$ The coefficient of a Carnot refrigerator does not depend on the temperatures B$)$ The work input to the Carnot refrigerator is maximized when the temperature difference between the reservoirs is minimized. C$)$ The heat extracted from the cold reservoir increases as the temperature of the hot reservoir increases. D$)$ The coefficient of performance of a Carnot refrigerator is given by $=$ TC TH$$T