This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fungal infections, Subject name: Dental
[{'content': 'All the following drugs are effective in the treatment of Pityriasis Versicolor except: \nSelect and explain. \nA. Selenium Sulphide, B. Ketoconazole, C. Griseofulvin, D. Clotrimazole', 'role': 'user'}, {'content': "Answer: C \nExplanation: Griseofulvin has no role in treatment of tinea versicolor. Griseofulvin is used systemically for dermotophytes (microsporum infection). It is ineffective topically. Treatment of Tinea/ Pityriasis versicolar Systemic (oral) Local (Shampoo/cream) New treatment Old Treatment Ketocoazole Itraconazole Micoconazole Econazole Ketoconazole Clotrimazole Whitfield's ointment (3% salicylic acid and 6% Benzoic acid) Selenium disulphide Sodium Thiosulphate", 'role': 'assistant'}]