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
Drug efficacy refers to 
Select and explain. 
A. Range of diseases in which the drug is beneficial, B. Maximal intensity of response that can be produced by the drug, C. The therapeutic dose range of the drug, D. The therapeutic index of the drug
B: Maximal intensity of response that can be produced by the drug
Answer: B: Maximal intensity of response that can be produced by the drug 
Explanation: None