<prompt> Best indicator of trend of Tuberculosis unaffected by current control measures is:-Annual risk of infectionPrevalence of TB infectionof primary drug resistanceof multidrug resistance  <response>: Annual risk of infection: Is the propoion of population which will be primarily infected with tuberculosis in course of 1 year. Is incidence of infection of TB. Is known as Tuberculosis conversion Index. Best indicator of trend of TB unaffected by current control measures. ARI: 1-2. For every 1 rise of ARI, there are 50 SS ve cases Lac population. 