<prompt> Which of the following is not an indicator of significant xerophthalmia problem in community?Night blindness 1Bitots spots 0.05Corneal ulcer0.05None of the above  <response>: Criteria Prevalence in 6 month to 6 years population Night blindness 1 Bitots spots 0.5 Corneal xerosisulceration 0.01 Corneal ulcer 0.05 Serum retinol 10 mcgdl 5 Ref: Park 22nd edition, page 570 