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
[{'content': 'In competetive antagonism \nSelect and explain. \nA. Vmax remains same, B. Potency remains same, C. Km decreases, D. Efficacy decreases', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Vmax corresponds to efficacy which remains same\xa0in competitive antagonism.\nKm corresponds to potency and in competitive antagonism Km increases, potency decreases.', 'role': 'assistant'}]