This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Which of the following is teratogenic: March 2011 \nSelect and explain. \nA. Folate, B. Cyanocobalamin, C. Vitamin A, D. Vitamin C', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C: Vitamin APharmacological doses of vitamin A are teratogenic and in pregnancy the daily dose must not exceed 6000-8000 IU.Synthetic analogues of vitamin A:TretinoinIsotretinoinEtretinateAcetretinTeratogenic drugsDrugs and medications:- Tobacco Caffeine- Drinking alcohol (ethanol) (fetal alcohol spectrum disorder),- Isotretinoin (13-cis-retinoic acid)- Temazepam- Nitrazepam- Aminopterin or methotrexate- Androgenic hormones Busulfan- Captopril, enalapril- Coumarin- Cyclophosphamide- Diethylstilbestrol-Phenytoin (diphenylhydantoin)Lithium- Methimazole- Penicillamine- Tetracyclines- Thalidomide- Trimethadione- Flusilazole- Valproic acidEnvironmental chemicals:- Polycyclic aromatic hydrocarbons (polynuclear aromatic hydrocarbons)- Polychlorinated biphenyls (PCBs)- Polychlorinated dibenzodioxins a.k.a dioxin,- Organic mercuryIonizing radiation:- Atomic weapons fallout (Iodine-131, uranium)- Background radiationDiagnostic x-rays- Radiation therapyInfections:- Cytomegalovirus- Herpes virus- Parvovirus B19- Rubella virus (German measles)- Syphilis- Toxoplasmosis An easy way to remember maternal infections is TORCH: Toxoplasmosis, Other agents, Rubella, CMV and HSV.Metabolic imbalance:- Alcoholism Diabetes- Folic acid deficiency- Iodine deficiency- Hypehermia', 'role': 'assistant'}]