This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharynx, Subject name: ENT
[{'content': 'Infection of submandibular space is seen in: \nSelect and explain. \nA. Ludwig angina, B. Vincent angina, C. Prinzmetal angina, D. Unstable angina', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (a) Ludwig angina(Ref. Scott Brown, 8th ed., Vol 3; 628; Stell & Maran, 5th ed., 229)Ludwig angina is infection of the submandibular space, i.e. floor of mouth.Vincent angina is ulcerative gingivitis along with involvement of the tonsils.Prinzmetal angina and unstable angina are the acute coronary syndromes.', 'role': 'assistant'}]