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
[{'content': 'Winging of scapula is due to paralysis of: \nSelect and explain. \nA. Nerve to trapezius, B. Nerve to serratus anterior, C. Nerve to latissimus dorsi, D. Nerve to pectoralis major', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. B Nerve to serratus anteriorRef: Gray's Anatomy 41st ed. P 819* Winging of scapula is due to paralysis of serratus anterior muscle.* Nerve supplying serratus anterior muscle: Long thoracic nerve (C5, 6, 7). Therefore long thoracic nerve palsy can also lead to winging of scapula.* Vascular supply: Serratus anterior is supplied by superior and lateral thoracic arteries, and by branches from the thoracodorsal artery after it divides in latissimus dorsi.", 'role': 'assistant'}]