A 23-Year-Old Man Comes to the Office Due to Left-Hand

A 23-year-old man comes to the office due to left-hand clumsiness. several hours ago, he was climbing a mountain but he lost his balance and fell while climbing. He tried to break the fall by grabbing a branch of a tree with his left hand. The patient did not have any head injury. On examination, he has difficulty with fine movements of the left hand. Which of the following structures is injured?

A) Axillary nerve
B) Long thoracic nerve
C) Lower trunk of the brachial plexus
D) Musculocutaneous nerve
E) Radial nerve
F) Suprascapular nerve