A test was considered for diagnosing a disease. Out of 80 positive cases with this test, 40 actually had no disease. Out of 9920 tested negative cases 9840 actually had no disease. Calculate the sensitivity of the test -: (A) 13%, (B) 33%, (C) 50%, (D) 99%
Answer is B. Ans. is 'b' i.e., 33%