This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pharmacology, Subject name: Pharmacology
[{'content': 'A patient was given a 200 mg dose of a drug IV, and 100 mg was eliminated during the first 2 hours. If the drug follows first-order elimination kinetics, how much of the drug will remain 6 hours after its administration \nSelect and explain. \nA. 100 mg, B. 75 mg, C. 50 mg, D. 25 mg', 'role': 'user'}, {'content': 'Answer: D \nExplanation: One half of the dose is eliminated in the first 2 hours so its elimination half-life equals 2 hours. With the passage of each half-life the amount in the body (or in the blood) will decrease to 50% of a former level. Thus, at 6 hours after administration, 3 half-lives have passed: (1) 200 mg to 100 mg, (2) 100 mg to 50 mg, and (3) 50 mg to 25 mg. Ref:- kd tripathi; pg num:-32 Plasma half-life:-', 'role': 'assistant'}]