Final answer:
A fixed restriction system operating with a refrigerant undercharge results in decreased cooling capacity, leading to compromised cooling performance and efficiency.
The correct option is d.
Step-by-step explanation:
The question pertains to a fixed restriction system operating with a refrigerant undercharge in a cooling system such as a refrigerator or an air conditioner. When a cooling system is undercharged with refrigerant, the most accurate description of its operation would be decreased cooling capacity.
This is because there is less refrigerant available to absorb and transport heat away from the space being cooled, resulting in a reduction of the system's overall cooling performance.
Undercharging means that there's insufficient refrigerant to absorb the maximum amount of heat possible, which results in a reduced temperature difference during the heat exchange process. Additionally, the compressor may not have to work as hard because there's less refrigerant to circulate,
which could be misconstrued as reduced compressor load, but this condition doesn't benefit the system's cooling efficiency. In reality, the compressor's workload may decrease because the system isn't operating at full capacity rather than due to any increase in operational efficiency.
The correct option is d.