This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper limb, Subject name: Anatomy
[{'content': 'How to test for the long thoracic nerve \nSelect and explain. \nA. Touch the opposite shoulder, B. Shoulder shrug, C. Raise the arm above the head, D. Lift an object from the ground', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The long thoracic nerve supplies the serratus anterior muscle. Its root value is C5, C6andC7. Serratus anterior is one of the main muscle for overhead abduction. So we can test the long thoracic nerve by asking the patient to abduct his arms overhead and forward pressure with the hands against a wall, or against resistance offered by examiner. B D Chaurasia 7th edition Page no : 46 and 47.', 'role': 'assistant'}]