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: Unknown
[{'content': 'Which of the following is not a constituent of mesorectum? \nSelect and explain. \nA. Pararectal lymph nodes, B. Inferior rectal artery, C. Middle rectal vein, D. Inferior mesenteric plexus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Refer: Gray’s Anatomy for Students, 1st edition, pg no: 418)\nMesorectal Fascia\n\xa0It contains:\n\nSuperior rectal artery and its branches.\nSuperior rectal vein and tributaries.\nLymphatic vessels and nodes along the superior rectal artery.\nBranches from the inferior mesenteric plexus which descend to innervate the rectum.\nLoose adipose connective tissue.', 'role': 'assistant'}]