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
Bronchospasm can be precipitated by: 
Select and explain. 
A. Adrenaline, B. Propranolol, C. Atropine, D. Salbutamol
B: Propranolol
Answer: B: Propranolol 
Explanation: None