A 30 year old male had severely itchy papula-vesicular lesions on both knees, elbows, upper back and buttocks for one year. Direct immunofluorescence staining of the lesions showed IgA deposition at dermoepidermal junction and dermal papilla. The most probable diagnosis is :
C i.e. Dermatitis herpetiformis
Pemphigus vulagris
Bullous pemphigoid
Dermatitis herpetiforms
Nummular eczema