This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
[{'content': 'The cavernous sinus does not communicate with the \nSelect and explain. \nA. Opthalmic vein, B. Internal jugular vein, C. External jugular vein, D. Pterygoid plexus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]