Through which duct does lymph from the lower body drain into the venous system?

Through which duct does lymph from the lower body drain into the venous system?

• A. Azygos vein
• B. Thoracic duct
• C. Right lymphatic duct
• D. Inferior vena cava

Answer: (B)

Lymph from the lower body uses the thoracic duct as its main drainage route into the venous system. It collects lymph from the abdomen and lower limbs (via lumbar trunks and the cisterna chyli) and then ascends in the thorax to empty into the left venous angle, where the left subclavian and internal jugular veins meet. The other structures aren’t lymphatic ducts: the azygos vein is a venous channel, the right lymphatic duct drains only the right upper quadrant, and the inferior vena cava is a major vein, not a lymphatic vessel.

Lymph from the lower body uses the thoracic duct as its main drainage route into the venous system. It collects lymph from the abdomen and lower limbs (via lumbar trunks and the cisterna chyli) and then ascends in the thorax to empty into the left venous angle, where the left subclavian and internal jugular veins meet. The other structures aren’t lymphatic ducts: the azygos vein is a venous channel, the right lymphatic duct drains only the right upper quadrant, and the inferior vena cava is a major vein, not a lymphatic vessel.