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
A patient Pushpa comes to you in the medicine emergency and you diagnose her to be suffering from severe CHF. You choose a drug 'Z' which is a short term ionotropic agent having selective adrenergic agonistic activity but lacking dopaminergic agonistic activity. What can be 'Z' ? 
Select and explain. 
A. Dopamine, B. Dobutamine, C. Amrinone, D. Salmeterol
B: Dobutamine
Answer: B: Dobutamine 
Explanation: None