A case-control study was [conducted on] ectopic pregnancy between 1993 and 2000 in France. It included 803 cases of ectopic pregnancy and 1,683 deliveries (controls) and was powerful enough to investigate all ectopic pregnancy risk factors. The main risk factors were infectious history (population attributable risk percent = 33%; adjusted odds ratio for previous pelvic infectious disease = 3.4, 95% percent confidence interval (CI): 2.4, 5.0) and smoking (population attributable risk percent = 35%; adjusted odds ratio = 3.9, 95% CI: 2.6, 5.9 for >20 cigarettes/day vs. women who had never smoked). The other risk factors were age, prior spontaneous abortions, history of infertility, and previous use of an intrauterine device. The use of adjusted odds ratios in the following study helped to correct which of the following potential issues :

A. Confounding

B. Differential misclassification

C. Information bias

D. Non-differential misclassification

E.Selection bias