This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
Cardioselective beta blockers is contraindicated in 
Select and explain. 
A. COPD, B. II & III degree heart block, C. Asthma, D. Tachycardia
B: II & III degree heart block
Answer: B: II & III degree heart block 
Explanation: (B) II & III degree heart block# Except for those drugs specifically approved for use in heart failure, beta blockers are contraindicated in heart failure patients> Side effects of beta-blockers are related to their cardiac mechanisms and include bradycardia, reduced exercise capacity, heart failure, hypotension, and atrioventicular (AV) nodal conduction block.> Beta-blockers are therefore contraindicated in patients with sinus bradycardia and partial AV block.> Non-selective beta-blockers are contraindicated in patients with asthma or chronic obstructive pulmonary disease which is not a contraindication for cardioselective beta blockers.