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: Skin
A 60 years old man presented with itchy tense blisters on normal looking skin and uicarial rash. Investigation done for the diagnosis: 
Select and explain. 
A. Direct immunofluorescence, B. Indirect immunofluorescence, C. Histopathology, D. Cytopathology
A: Direct immunofluorescence
Answer: A: Direct immunofluorescence 
Explanation: Ans. a. Direct immunofluorescence A 60 years old man presented with itchy tense blisters on normal looking skin and uicarial rash. This patient is suffering from pemphigoid. Investigation done for the diagnosis direct immunofluorescence.