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: Orthopaedics
[{'content': 'The features of Achondroplasia inlcude all,except -a) Defective headb) Mental retardationc)  Autosomal recessived) Familial \nSelect and explain. \nA. bc, B. c, C. ac, D. ad', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Achondroplasia has an autosomal dominant pattern of inheritance.\nIntelligence and sexual development is normal.\nSkull is large with a bulging vault and forehead.', 'role': 'assistant'}]