This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'In case of IVC obstruction, the collateral which opens up are all except \nSelect and explain. \nA. Superior epigastric & inferior epigastric vein, B. Azygos& ascending lumbar vein, C. Superficial epigastric & ileolumbar vein, D. Lateral thoracic veins & preveebral vein', 'role': 'user'}, {'content': "Answer: C \nExplanation: Superficial epigastric vein drains into the femoral vein&ileo lumbar vein drains into common iliac vein Ref: Gray's 39e/p10", 'role': 'assistant'}]