This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Burn), Subject name: Surgery
Green coloured i.v. cannula, the size is - 
Select and explain. 
A. 18, B. 20, C. 22, D. 24
A: 18
Answer: A: 18 
Explanation: Ans. is 'a' i.e., 18Colour coding of iv cannuleSizeColour14 gOrange16 gGrey18 gGreen20 gPink22 gBlue24 gYellow/lime