This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head & Neck, Subject name: Anatomy
A patient with enlarged cervical lymph nodes has a malignant tumor of the cecum. Which of the following lymph nodes of the neck is most frequently associated with malignant tumors of the gastrointestinal tract? 
Select and explain. 
A. Left inferior deep cervical, B. Left supraclavicular, C. Right inferior deep cervical, D. Right supraclavicular
B: Left supraclavicular
Answer: B: Left supraclavicular 
Explanation: The supraclavicular lymph node on the left side is associated with the thoracic duct. The thoracic duct receives lymph from below the diaphragm, including the gastrointestinal tract. Malignant cells that travel up the thoracic duct are known to involve the left supraclavicular lymph node.