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
Hyperextension of PIP and Flexion of DIP is seen in which deformity 
Select and explain. 
A. Swan neck, B. Mallet finger, C. Lumbricals paralysis, D. Boutonniere's
A: Swan neck
Answer: A: Swan neck 
Explanation: None