Answer:
Heat pump
Step-by-step explanation:
COP:
As we know that COP can be defines as the ratio of desired effect to the work in put.
The desired effect can be different for heat pump our desired effect to heat the space and for refrigeration our desired effect is cooled the space.
So


When heat pump and refrigerator are operating with same temperature limits then from expression we can say that
COP of heat pump = 1 + COP of refrigeration.