This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Agonist is having 
Select and explain. 
A. Affinity with intrinsic activity 0, B. Affinity with intrinsic activity 1, C. Affinity with intrinsic activity -1, D. None
A: Affinity with intrinsic activity 0
Answer: A: Affinity with intrinsic activity 0 
Explanation: Ref-KDT 6/e p41 Agonist have intrinsic acriacti 1 because Intrinsic activity is a measure of the ability of a drug that is bound to the receptor to generate an activating stimulus and produce a change in cellular activity. Both agonists and antagonists can bind to a receptor. However, only agonist molecules can activate the receptor.