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: Psychiatry
[{'content': 'A 39 years old male patient presents with waxy flexibility, negativism and rigidity. Most probable diagnosis is? \nSelect and explain. \nA. Excitatory catatonia, B. Stuporous catatonia, C. Paranoid schizophrenia, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. Stuporous catatonia Stuporous (retarded) catatonia : Characterized by extreme retardation of psychomotor function, which includes mutism, rigidity, negativism, posturing, echolalia, Echopraxia, Catalepsy (waxy flexibility), ambitendency, gegenhalten, streotypies, stupor, Mannerism, Grimicing, Automatic obedience, and verbigeration.', 'role': 'assistant'}]