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: Physiology
Na+ &/or IC+ is/are involved in mechanism of action of which of the following receptor (s): 
Select and explain. 
A. 5-HT3 receptor, B. Nm receptor, C. Nn receptor, D. All
D: All
Answer: D: All 
Explanation: A,B,C All