This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cytotoxic Anticancer Drugs, Subject name: Pharmacology
[{'content': 'Pentostatin acts by inhibiting: \nSelect and explain. \nA. RNA dependent DNA polymerase, B. Aldolase, C. Adenosine deaminase, D. Adenylyl cyclase', 'role': 'user'}, {'content': 'Answer: C \nExplanation: * Pentostatin and cilastatin are not statins i.e. these do not act by inhibiting HMG-CoA reductase. * Pentostatin acts by inhibiting adenosine deaminase. * It is used for the treatment of hairy cell leukemia. * Drug of choice for hairy cell leukemia is cladribine.', 'role': 'assistant'}]