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
Damage to C7 nerve root causes weakness of - 
Select and explain. 
A. Elbow flexion, B. Supination, C. Finger abduction, D. Wrist flexion
D: Wrist flexion
Answer: D: Wrist flexion 
Explanation: None