This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (R.B.C), Subject name: Pathology
The best suited anticogulant for osmotic fragility test is: 
Select and explain. 
A. Heparin, B. EDTA, C. Trisodium citrate, D. Potassium oxalate
A: Heparin
Answer: A: Heparin 
Explanation: Ans. (a) Heparin(Ref: Dacie 11th/pg246)Best suited anticogulant for osmotic fragility test is Heparin.Heparinized venous blood or defibrinated blood may also be usedOxalated or citrated blood is not suitable because of the additional salts added to it.