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': 'Posterior wall of rectus sheath below the level of an anterior superior iliac spine is formed by \nSelect and explain. \nA. Internal oblique, B. Lacunar ligament, C. Fascia transversalis, D. Transversus abdominis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The Rectus, where its posterior sheath is deficient (below arcuate line), is separated from the peritoneum only by the transversalis fascia, in contrast to the upper layers, where pa of the internal oblique also runs beneath the rectus. Because of the thinner layers below, this region is more susceptible to herniation.', 'role': 'assistant'}]