This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
Test normally undeaken to demonstrate the presence of collateral circulation of hand is NOT RELATED-SURGERY 
Select and explain. 
A. Kety Schmidt test, B. Allen's test, C. Sellick's test, D. Swan Ganz test
B: Allen's test
Answer: B: Allen's test 
Explanation: Allen's test is done to determine the presence of collateral circulation of hand before cannulating radial aery.