The casing is the .... Of the pump housing

• A. Hollow inner
• B. Pump housing
• C. The outer cover
• D. Outer shell

Answer: (D)

The casing is the outer shell of the pump housing. In pump terminology, the housing includes the parts that surround and guide the moving parts, and the casing is the external boundary that encloses the internal components and defines the flow path. It provides the structural boundary, includes the suction and discharge ports, and is the part you normally access for maintenance. The hollow inner refers to the cavity inside, not the enclosing shell; the outer cover isn’t the standard term for this boundary, and the pump housing is a broader assembly, not the specific exterior enclosing layer. So the outer shell best describes the casing.