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: Anatomy
Which of the following is not a tributary of azygos vein? 
Select and explain. 
A. Right posterior intercostal, B. Right superior intercostal, C. Left superior intercostal, D. Accessory hemiazygos
C: Left superior intercostal
Answer: C: Left superior intercostal 
Explanation: Tributaries of Azygos vein

Right superior intercostal vein
Right posterior intercostal veins (5 to 11)
Hemiazygos vein
Accessory hemiazygos vein
Right bronchial vein
Esophageal, mediastinal and pericardial veins.