This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Schizophrenia Spectrum and Other Psychotic Disorders, Subject name: Psychiatry
Waxy flexibility is a characteristic sign of: 
Select and explain. 
A. Excitatory catatonia, B. Stuporous catatonia, C. Obsessive compulsive disorder, D. Paranoid schizophrenia
B: Stuporous catatonia
Answer: B: Stuporous catatonia 
Explanation: Waxy flexibility is a sign of catatonia. In waxy flexibility, when examiner makes a passive movement on patient, there is a feeling of plastic resistance which resembles bending of a soft wax candle. It is seen in stupors catatonia more commonly. In excitatory catatonia, instead of stupor, patient shows increased levels of goal less activity.