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': 'Vidian nerve is formed by union of? \nSelect and explain. \nA. Superficial petrosal nerve and deep petrosal nerve, B. Greater petrosal nerve and superficial petrosal nerve, C. Greater petrosal nerve and deep petrosal nerve, D. Greater petrosal nerve and external petrosal nerve', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Greater petorsal nerve units with deep petrosal nerve to form nerve to pterygoid canal (also called vidian nerve).', 'role': 'assistant'}]