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
Which of the following is used in exocytosis? 
Select and explain. 
A. Ca, B. Mg, C. Na, D. K
A: Ca
Answer: A: Ca 
Explanation: Ans. (a) CaExocytosis is a calcium dependent process where in the cellular contents are moved out of the cell in the form of vesicles (Cell Vomiting)