Example of case control study (risk factor and disease/outcome) ?

Ans. is `d' i.e., All of the above Impoant risk factors and their outcomes/diseases which have been studied by case-control study are :- Cigarette smoking and lung cancer. Maternal smoking and congenital malformation. Radiation and leukemia. OCP used and hepatocellular carcinoma. Herpes-simplex and Bells palsy. Aificial sweeteners and bladder cancer. DES exposure in fetal life and vaginal adenocarcinoma. OCP use and thromboembolic disease. Thalidomide use in pregnancy and teratogenicity.