This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adverse Drug Effect, Subject name: Pharmacology
[{'content': 'Phacomelia is seen due to which drug? \nSelect and explain. \nA. Thalidomide, B. Dexamethasone, C. Chlorambucil, D. Betamethasone', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Thalidomide * Has been explained in previous sessions", 'role': 'assistant'}]