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: Surgery
[{'content': "Which of the following best represents `ranula'? \nSelect and explain. \nA. A type of epulis, B. A thyroglossal cyst, C. Cystic swelling in the floor of mouth, D. A type of mucus retention cyst", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]