This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'Erythematous lesions with Collarets of scales on trunk \nSelect and explain. \nA. Pityriasis rubra, B. Pityriasis rosea, C. Pityriasis versicolor, D. Pityriasis alba', 'role': 'user'}, {'content': 'Answer: B \nExplanation: .', 'role': 'assistant'}]