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: Gynaecology & Obstetrics
Obsolete method for testing tubal patency is : 
Select and explain. 
A. Hystero salpingogram, B. Chromo salpingogram, C. Rubin's test, D. None of the above
C: Rubin's test
Answer: C: Rubin's test 
Explanation: Rubin's test