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: Biochemistry
[{'content': 'Competitive enzyme inhibition will cause: \nSelect and explain. \nA. Decrease of Km and increase of Vmax, B. Increase of Km and increase of Vmax, C. Decrease of Km and decrease of Vmax, D. Increase of Km and unchanged Vmax', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]