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What is Most characteristic finding of retinitis pigmentosa –a) Ring scotomab) Peripheral field defectc) Central scotomad) Diplopia and explain in detail?
Ring scotoma is a peripheral field defect, which is characteristic finding of retinitis pigmentosa.

"Peripheral vision loss is hallmark of retinitis pigmentosa, with the classic ring scotoma 30 -50 degree from fixation" __ Pediatric retina by Hartnett.
"The ring scotoma is the characteristic field defect of retinitis pigmentosa". —Harley's pediatric ophthalmology