This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid & Electrolyte, Subject name: Surgery
[{'content': 'Which of the following is not used for intravascular volume maintenance is: \nSelect and explain. \nA. Hydroxy ethyl starch, B. Dextran, C. Erythropoetin, D. Gelatin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) ErythropoetinRef: Crystalloids versus colloids in fluid resuscitation: a systematic review. Crit Care Med.* Colloids increase intravascular volume* Colloids are dextran, gelatin, hydroxyethyl starch.', 'role': 'assistant'}]