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
Action affected in BENNET'S fraction of thumb? 
Select and explain. 
A. Flexion of thumb, B. Abduction  of thumb, C. Opposition  of thumb, D. Adduction  of thumb
C: Opposition  of thumb
Answer: C: Opposition  of thumb 
Explanation: Bennet's fraction is the fracture of base of 1st metacarpal. Opponens pollicis has its insertion to 1st metacarpal and hence its action is lost in the following fracture.