Which of the conditions listed could cause excessively low refrigerant pressure at the compressor suction of a TXV controlled refrigeration system?

Correct Answer: Option B — The system is low on refrigerant.

A depleted refrigerant charge starves the thermostatic expansion valve, reducing mass flow into the evaporator. This causes rapid evaporation, low vapor density, and an excessively low suction pressure as the compressor evacuates the low side.