A 25-Year Old Man Is Brought to the Emergency Department

A 25-year old man is brought to the emergency department after he fell from a high tree. The patient landed on his upper arm. The patient is in pain. His blood pressure is 120/78 Hg and his pulse is 120/min. On physical examination, the patient has tenderness, swelling, and erythema in the upper arm. Radiological imaging shows midshaft fracture of the humerus. This patient is at risk to lose which of the following functions?

A) Abduction of the fingers
B) Adduction of the thumb
C) Extension of the wrist
D) Flexion of the wrist
E) Opposition of the thumb