This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Ophthalmology
Most common nerve involved in herpes zoster ophthalmicus is 
Select and explain. 
A. Frontal, B. Lacrimal, C. Nasaciliary, D. Oculomotor
A: Frontal
Answer: A: Frontal 
Explanation: HZO is an acute infection of Gasserian ganglion of the fifth cranial nerve by the varicella-zoster virus (VZV). VZV is a DNA virus and produces acidophilic intranuclear inclusion bodies. It is neurotropic in nature. In HZO , frontal nerve is more frequently affected than the lacrimal and nasociliary nerves. Ref: khurana 6 th edition page no.104