This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General, Subject name: Physiology
Most diffusible ion across membrane: 
Select and explain. 
A. Na+, B. K+, C. Cl-, D. None
B: K+
Answer: B: K+ 
Explanation: Ans. (b) K+(Ref: Ganong, 25th ed/p.35)At rest, cell membrane is freely permeable for potassium ionThis is the reason behind development of RMP which is due to potassium ion