This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Body Fluids, Subject name: Physiology
[{'content': 'Potassium in which compartment is responsible for cardiac and neural function? \nSelect and explain. \nA. Intracellular, B. Extracellular, C. Intravascular, D. Extravascular', 'role': 'user'}, {'content': 'Answer: A \nExplanation: ANSWER: (A) IntracellularREF: Guyton\'s physiology 11th edition page 46 & 358, Ganongs 22nd edition chapter 1\'\'Potassium cations are important in neuron (brain and nerve) function, and in influencing osmotic balance between cells and the interstitial fluid"* Potassium is the most abundant cation in intracellular fluid.* Phosphate is the most abundant intracellular anion.* Sodium is the most abundant extracellular cation.* Chloride is the most abundant extracellular anion.', 'role': 'assistant'}]