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
The features of Achondroplasia inlcude all,except -a) Defective headb) Mental retardationc)  Autosomal recessived) Familial 
Select and explain. 
A. bc, B. c, C. ac, D. ad
A: bc
Answer: A: bc 
Explanation: Achondroplasia has an autosomal dominant pattern of inheritance.
Intelligence and sexual development is normal.
Skull is large with a bulging vault and forehead.