This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Integrated QBank, Subject name: Anatomy
[{'content': 'A 40-year-old male patient presented to the ER with pain and deformity in the left arm after having a fall 2 hours ago. The doctor ordered an x-ray of the affected area. The nerve most likely involved in the above condition supplies which of the following marked muscles: - \nSelect and explain. \nA. Muscle B, B. Muscle A, C. Muscle D, D. Muscle C', 'role': 'user'}, {'content': 'Answer: B \nExplanation: This is a case of fracture of surgical neck of humerus. The nerve involved is axillary nerve. Muscle supplied by axillary nerve are teres minor and deltoid.', 'role': 'assistant'}]