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
Commonest presentation of congenital dislocation of the knee is - 
Select and explain. 
A. Varus, B. Valgus, C. Flexion, D. Hyperextens ion
D: Hyperextens ion
Answer: D: Hyperextens ion 
Explanation: The patient presents with hyperextension deformity of the knee.