This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abdomen and pelvis, Subject name: Anatomy
[{'content': 'Structure contained within rectus sheath are all except \nSelect and explain. \nA. Internal thoracic aery, B. Superior epigastric aery, C. Inferior epigasbric aery, D. Rectus abdominis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The rectus sheath is formed by the aponeuroses of the transverse abdominal and the external and internal oblique muscles. It contains the rectus abdominis and pyramidalis muscles. It can be divided into anterior and posterior laminae. image ref - researchgate.net', 'role': 'assistant'}]