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
β - blockers masks all the symptoms of hypoglycemia except 
Select and explain. 
A. Sweating, B. Increased heart rate, C. Hypertension, D. None of the above
A: Sweating
Answer: A: Sweating 
Explanation: β - blockers masks all sympathetic adrenergic symptoms, but sweating is caused because of sympathetic cholinergic activity.