This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pharmacology
Which of the following is fastest calcium lowering agents 
Select and explain. 
A. Calcitonin, B. Plicamycin, C. Etidronate, D. Zoledronate
A: Calcitonin
Answer: A: Calcitonin 
Explanation: Refer CMDT 2010/801 Bisphoshonates are the treatment of choice for hypercalcemia of malignancy but require 48-72 hours before reaching full therapeutic effect Calcitonin may be helpful to treat hypercalcemia before the onset of action of bisphoshonates