<prompt> Which of the following drug can result in teratogenic effect shown in the diagram if given during pregnancy?NiacinRetinoic acidThiamineFolic acid  <response>: Ans. B Retinoic acidRef: Katzung 13the p1042; KDT 8the p154Retinoic acid and isotretinoin are well known teratogens. These can result in cleft lip and other congenital anomalies. 