Ophthalmology Tumors bc2764c8 Knudson's two stage hypothesis is for- A Glaucoma B Retinoblastoma C Optic glioma D Meningioma High-Yield Explanation *Deletion or inactivation of RB gene by two mutations (knudson's two hit hypothesis) results in occurence of retinoblastoma. Ref: Khurana 7th/e p.314.