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: Biochemistry
[{'content': '. Anticoagulant used to estimate glucose from a sample sent from PHC is: \nSelect and explain. \nA. EDTA, B. Calcium oxalate, C. Potassium oxalate + NaF, D. Sodium citrate', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Potassium oxalate + NaF', 'role': 'assistant'}]