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
Therapeutic drug monitoring of plasma concentrations of antihypertensive drugs is NOT practiced because: 
Select and explain. 
A. Determination of plasma level of these drugs is quite tedious and long process, B. It is easier to measure the effect of these drugs, C. Antihypertensive effect do not increase linearly with the dose, D. All antihypertensive drugs are prodrugs
B: It is easier to measure the effect of these drugs
Answer: B: It is easier to measure the effect of these drugs 
Explanation: None