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: Gynaecology & Obstetrics
[{'content': 'Isotretinoin embryopathy is characterized by all except \nSelect and explain. \nA. Venticulomegaly, B. Microtia, C. Conotruncal heart defects, D. Thymic hyperplasia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Isotretinoin embryopathy is characterized by thymic hypoplasia or aplasia.', 'role': 'assistant'}]