Which of the following lists the hollow organs of the body?

• A. Heart, lungs, and liver
• B. Stomach, intestines, and urinary bladder
• C. Brain and spinal cord
• D. Spleen and pancreas

Answer: (B)

Hollow organs are structures that have a central cavity, or lumen, which can be filled with contents and can distend as they fill. The stomach, intestines, and urinary bladder fit this description, as each has a lumen lined with mucosa and serves as a reservoir for material—food, waste, or urine. The heart, while it contains blood within chambers, is mainly a muscular pump rather than described as a hollow organ in this context. The lungs contain air spaces but are not grouped with hollow organs in this sense, and solid organs like the liver, spleen, pancreas, brain, and spinal cord lack a persistent lumen for contents. Therefore, the list that matches hollow organs is stomach, intestines, and urinary bladder.