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: Anatomy
First carpometacarpal joint is a - 
Select and explain. 
A. Hinge joint, B. Saddle joint, C. Elipsid joint, D. Synol
B: Saddle joint
Answer: B: Saddle joint 
Explanation: B i.e. Saddle