This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Embryology and abdominal wall layer, Subject name: Anatomy
[{'content': 'Smallest abdominal muscle is: \nSelect and explain. \nA. External oblique, B. Internal oblique, C. Transversalis, D. Rectus abdominis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The transverse abdominis is the smallest of the four abdominial muscles and lies deep to the others.', 'role': 'assistant'}]