This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Retina, Subject name: Ophthalmology
Diagnosis of CMV retinitis is primarily by? 
Select and explain. 
A. Fundoscopy, B. Retinal biopsy, C. CMVDNA, D. ELISA
A: Fundoscopy
Answer: A: Fundoscopy 
Explanation: Ans. (a) FundoscopyRef: Kanski 7/e, chapter 11, Intraocular drug delivery by glenn J. Jaffe p 330