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
True about esmolol is: 
Select and explain. 
A. It has no intrinsic sympathomimetic activity, B. It is a cardioselective β–blocker, C. It can precipitate heart failure, D. All of these
D: All of these
Answer: D: All of these 
Explanation: None