What is the device that is opposite of the evaporator where heat is rejected?

The device that is opposite of the evaporator and where heat is rejected is the condenser. In a refrigeration cycle, the evaporator absorbs heat from the surroundings, causing a refrigerant to evaporate into a gas. This process removes heat from the area being cooled. The condenser, on the other hand, is where the refrigerant gas is compressed and then released, allowing it to dissipate heat into the environment as it converts back into a liquid state.

This heat rejection process is crucial for maintaining the efficiency of the refrigeration cycle, as it allows the refrigerant to cool down and be reused in the evaporator. The role of the condenser is thus vital in the system, and its function is directly opposite to that of the evaporator, making it the correct answer for this question.