Rate of elimination of drug is:

Ans: A (Clearance) Ref: Basic & Clinical Pharmacology, Katzung 12th ed. P.38Explanation:Clearance of a drug is the factor that predicts the rate of elimination in relation to the drug concentrationClearance = rate of elimination/plasma concentrationBiotransformation: It is a chemical modification ( or modifications) made by human body on a chemical compound.Drug biotransformations have 2 classical reactions: Phase I and Phase II. (See the following figure)Bioavailability: It is the fraction of administered drug that reaches the systemic circulation. Bioavailability is expressed as the fraction of administered drug that gains access to the systemic circulation in a chemically unchanged form.