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What is Stage X3B refers to the following in the classification of vitamin A deficiency: and explain in detail?
d. Keratomalacia(Ref: Nelson's 20/e p 3 IB-320, Ghai B/e p 111-112)WHO classification of Vitamin A deficiency:IndicatorCategoryNight blindnessXNConjunctival xerosisX1ABitot's spotsX1BCorneal xerosisX2Corneal ulcerationX3AKeratomalaciaX3BXerophthalmia-related corneal scarsXS