Answer- D. Routine checkup of all operated casesTb evaluates postoperative vision effects after cataract extraction surgery under NPCB, routine checkup of all operated cases is used.Strategies under National Programme for Control of Blindness (NPCB)Improving follow-up services of cataract operated patients and treating other causes of epidemics like glaucomaShift eye camp approval to a fixed surgical approach and from conventional surgery to IOL installation for better quality of postoperative vision to operated patients.Expand World Bank Project activities like construction of dedicated eye operation theatres, eye wards at district level, training of other ophthalmic equipment's to the work community.To strengthen paicipants of voluntary organizations in the programme.To enhance the coverage of eye care services in the tribal and underserved areas.Screening of refractive errors in school going children.