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
[{'content': 'Among the following muscles, the one that is found in the first layer of the sole is: \nSelect and explain. \nA. Adductor hallucis, B. Flexor digitorum brevis, C. Flexor digiti minimi brevis, D. Flexor hallucis longus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Flexor digitorum brevis', 'role': 'assistant'}]