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
3 days post colle's fracture. a person is unable to extend his thumb due to 
Select and explain. 
A. Rupture of extensor pollicis longus tendon, B. Volkman's Ischemic contracture, C. Radial nerve injury, D. Finger stiffness
A: Rupture of extensor pollicis longus tendon
Answer: A: Rupture of extensor pollicis longus tendon 
Explanation: None