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: Surgery
[{'content': 'Incidence of undescended testis in preterm infants is: \nSelect and explain. \nA. <5%, B. 10%, C. 20%, D. 30%', 'role': 'user'}, {'content': "Answer: D \nExplanation: The incidence of undescended testes is approximately 30% in preterm infants. Remember that undescended testis is more common in preterm when compared with term babies. Ref: Schwaz's principle of surgery 9th edition, chapter 39.", 'role': 'assistant'}]