This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
[{'content': 'Which of the following major minerals is a component of biological membranes? \nSelect and explain. \nA. Calcium, B. Sodium, C. Phosphorus, D. Potassium', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The plasma membrane consists of a complex lipid bilayer, phosphate and carbohydrate components, and a large number of proteins embedded in the membrane that connect the inner milieu of the cell with the external environment. .', 'role': 'assistant'}]