The correct answer is D) A pump room is not necessary. Deep well cargo pumps are designed to be installed directly in the cargo tank, eliminating the need for a separate pump room. This configuration allows for a more compact and efficient cargo handling system on ships. The pump motor is located at the top of the shaft, and the impeller is at the bottom, submerged in the cargo. Special priming provisions are required due to the submerged nature of the pump. Therefore, option D is the correct statement, while options A, B, and C are incorrect.