###Rationale: Ans. A: Nightblindness more than 1% Criteria for determining the "Xerophthalmia problem" in a community includes prevalence o f night blindness of more than 1.0% Prevalence criteria for determining the xerophthalmia problem Nightblindness: More than 1% Bitot's spots: More than 0.5% Corneal xerosis/corneal ulceration/ keratomalacia: More than 0.01% Corneal ulcer: More than 0.05% Serum retinol (less than 10 mcg/ dB: More than 5%

###Answer: OPTION A IS CORRECT.
###Question: Which of the following prevalence rates indicates xerophthalmia problem in the community: September 2011
###Options:
A. Nightblindness more than 1%
B. Corneal xerosis more than 1%
C. Bitot spot's more than 1%
D. Conjunctival xerosis more than 0.5%
