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: Pathology
[{'content': 'Haematocrit is the ratio of: \nSelect and explain. \nA. WBC to whole blood, B. Platelets to whole blood, C. RBCs to whole blood, D. Total blood cells to plasma', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Haematocrit (also known as packed cell volume) is the volume percentage (%) of red blood cells in blood.', 'role': 'assistant'}]