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: Pharmacology
For partial agonist value of intrinsic activity should be: 
Select and explain. 
A. 1, B. 0, C. Between 0 and +1., D. -1
C: Between 0 and +1.
Answer: C: Between 0 and +1. 
Explanation: None