<prompt> Which of the following prevalence rates indicates xerophthalmia problem in the community: September 2011Nightblindness more than 1Corneal xerosis more than 1Bitot spots more than 1Conjunctival xerosis more than 0.5  <response>: 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 Bitots spots: More than 0.5 Corneal xerosiscorneal ulceration keratomalacia: More than 0.01 Corneal ulcer: More than 0.05 Serum retinol less than 10 mcg dB: More than 5 