In a case-control study, a researcher found no association between exposure to A and disease B. Later she found out that there was a misclassification when measuring exposure to A, in both cases and controls. What is a potential explanation for the results (no association) of this case-control study? a. Differential misclassification
b. Confounding
c. Selection bias
d. Effect-modification
e. Nondifferential misclassification