This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anatomy
The longest duration of action of insulin preparation is obtained with 
Select and explain. 
A. Crystal zinc insulin, B. Insulin zinc suspension (Semilente), C. Protamine zinc insulin, D. Isophane insulin
C: Protamine zinc insulin
Answer: C: Protamine zinc insulin 
Explanation: (Refer Q 17)