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
Which of the following is a high ceiling diuretic ? 
Select and explain. 
A. Furosemide, B. Spironolactone, C. Acetazolamide, D. Thiazide
A: Furosemide
Answer: A: Furosemide 
Explanation: Ans. is 'a' i.e., Furosemide o Loop diuretics are called high ceiling diuretics because, progressive increase in dose is matched by increasing diuresis, i.e. they have a high ceiling effect. o Furosamide is a loop diuretics.