What is the state of the refrigerant entering the condenser?

The correct choice reflects that the refrigerant entering the condenser is in a state of high pressure and is highly superheated vapor.

In the refrigeration cycle, the refrigerant exits the compressor as a high-pressure gas. At this stage, it is typically also highly superheated due to the work done by the compressor, which increases its temperature and pressure. When this superheated vapor reaches the condenser, it is still at a high pressure, which is necessary to allow for efficient heat transfer as the refrigerant condenses.

The condenser's role is to remove heat from the refrigerant, causing it to undergo a phase change from a vapor to a liquid. Therefore, before entering the condenser, the refrigerant must be in a state that allows it to transition effectively as it releases heat. If it were in a saturated or subcooled state, it would not be as efficient in absorbing heat during the compression phase, nor would it align with the physical principles of the refrigeration cycle wherein compression results in an increase in pressure and enthalpy.

This understanding highlights the importance of each phase of refrigerant in the cycle and supports the notion that the refrigerant entering the condenser is a high-pressure, highly superheated vapor.