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
which of the following can also be utilized to know whether a drug is a competitive or non-competitive inhibitor : 
Select and explain. 
A. Potency., B. DRC., C. Efficacy., D. All of the above.
B: DRC.
Answer: B: DRC. 
Explanation: In a competitive inhibitor, the curve will shift to right while in non-competitive inhibitor there will be flattening of DRC.