This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drugs, Subject name: Medicine
[{'content': 'Which one of the following medications is most likely to be responsible for this appearance? \nSelect and explain. \nA. Clarithromycin, B. Dexamethasone, C. Doxorubicin, D. Efavirenz', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer C. DoxorubicinSeveral chemotherapeutic drugs (including doxorubin and cyclophosphamide) cause dyspigmentation. Other groups of drugs that cause this problem include antimalarials, amiodarone, heavy metals (but not iron), tetracyclines, and antipsychotics.', 'role': 'assistant'}]