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
Metoprolol is preferred over Propranolol as it: September 2010 
Select and explain. 
A. Is more potent in blocking beta-1 receptors, B. Is more potent in blocking beta-2 receptors, C. Is more effective in suppressing essential tremors, D. Impairs exercise capacity
A: Is more potent in blocking beta-1 receptors
Answer: A: Is more potent in blocking beta-1 receptors 
Explanation: Ans. A: Is more potent in blocking beta-1 receptors Metoprolol is cardioselective beta blocker, more potent in blocking beta-1 than beta-2 adrenergic receptors.