According to WHO, the prevalence of leprosy is a major public health problem when the incidence is more than:

Ans is 'c' i.e. 0.01% Under the NLEP the goal is to reduce case load to 1 or less than I per 10000 population (i.e. 0.01)Thus leprosy will be a public health problem if its incidence is more than 0.01%.I admit, I haven't found the answer, written in any text but this is the inference I have drawn from Park.Case finding methods in leprosy control ProgrammeContact surveys* are done where the prevalence of leprosy is < 1 case per 1000populationGroup survey* : where prevalence is 1/1000 or higherMass survey*: areas where prevalence is about 10 or more per 1000population.