A diagnostic test has a sensitivity of 90% and a specificity of 99% in detecting a certain disease. From this we can conclude that
A. the false positive rate of this test is 1%
B. the false negative rate of this test is 1%
C. the positive predictive value of this test is 90%
D. the negative predictive value of this test is 90%
E. this test would be a useful screening test for this disease
Answer: A