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
How to test for the long thoracic nerve? 
Select and explain. 
A. Touch the opposite shoulder, B. Shoulder shrug, C. Raise the arm above the head, D. Lift an object from the ground
C: Raise the arm above the head
Answer: C: Raise the arm above the head 
Explanation: Long thoracic nerve innervates Serratus anterior. Serratus anterior originates from outer surface of upper 8 ribs and inserts onto inferior angle and medial border of scapula.
Actions
-        It rotates the scapula to help in overhead abduction.
-        Steady the scapula to carry weight.
-        Pushing of arm forward in horizontal position.
-        Helps in forced inspiration.