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
The Term Clearance of drug means: 
Select and explain. 
A. Unit volume of plasma which is cleared off drug in unit of time, B. Amount of drug excreted in urine, C. Amount of drug metabolised in unit of time, D. Fraction of dose administered only
A: Unit volume of plasma which is cleared off drug in unit of time
Answer: A: Unit volume of plasma which is cleared off drug in unit of time 
Explanation: Unit volume of plasma which is cleared off drug in unit of time