<prompt> A 39 years old male patient presents with waxy flexibility, negativism and rigidity. Most probable diagnosis is?Excitatory catatoniaStuporous catatoniaParanoid schizophreniaNone  <response>: 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. 