This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: DNB 2018, Subject name: Pharmacology
[{'content': 'Tolterodine used in overactive bladder acts by blocking which of the following receptors? \nSelect and explain. \nA. M1, B. M2, C. M3, D. M4', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Selective M3 antagonists acting on GIT and bladder Selective M3 antagonists acting only on bladder (vesicoselective) Derifenacin Oxybutynin Solifenacin Flavoxate Tolterodine Trospium chloride', 'role': 'assistant'}]