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
b1 selective agonist is - 
Select and explain. 
A. Terbutaline, B. Albuterol, C. Dobutamine, D. Isoetharine
C: Dobutamine
Answer: C: Dobutamine 
Explanation: Ans. is 'c' i.e., Dobutamine o Dobutamine is a relatively selective DI agonist. Though it acts on both a and receptors, the only prominent action of clinically employed doses is its [3, action, i.e. an increase in force of cardiac contraction and output, without a significant change in HR., BP and Peripheral resistance.