This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid Gland, Subject name: Pediatrics
[{'content': 'Most common cause of congenital hypothyroidism: (Repeat) \nSelect and explain. \nA. Thyroid dysgenesis, B. Maternal antibodies, C. Inborn errors of thyroid hormone defects, D. Maternal iodine deficiency', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: A (Thyroid dysgenesis) Ref: Nelsons Textbook of Pediatrics. 19th Edition. Pg.1895Explanation:"Most cases of congenital hypothyroidism results from thyroid dysgenesis "(Ref: Nelson)Refer 2013 Pediatrics Question Explanation', 'role': 'assistant'}]