This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper Extremity, Subject name: Anatomy
Choose the appropriate lettered site or structure in the following radiograph of the wrist and hand. Destruction of the structure indicated by the letter E most likely causes weakness of which of the following muscles? 
Select and explain. 
A. Flexor carpi radialis, B. Palmaris longus, C. Flexor carpi ulnaris, D. Brachioradialis
C: Flexor carpi ulnaris
Answer: C: Flexor carpi ulnaris 
Explanation: (c) The hook of hamate and the pisiform provide insertion for the flexor carpi ulnaris.