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
All of the following structures passes through the guyon's canal, EXCEPT? 
Select and explain. 
A. Ulnar nerve, B. Ulnar aery, C. Ulnar vein, D. Flexor carpi ulnaris
D: Flexor carpi ulnaris
Answer: D: Flexor carpi ulnaris 
Explanation: Guyon's canal is located superficially on the ulnar side of the carpus. The contents of this canal are the ulnar nerve which divides into superficial and deep palmar branch, ulnar aery and vein. Guyon's canal is bounded on the ulnar side by the pisiform, the hook of hamate, and hypothenar muscles. On the dorsal side it is bounded by flexor retinaculum and on the palmar side by the palmar carpal ligament.