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: Dental
[{'content': 'Exposure to sunlight can precipitate \nSelect and explain. \nA. Cholasma, B. Discoid LE, C. Dermatitis herpetiformis, D. Lupus vilgaris', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Exposure to sunlight is a predisposing factor but only 4% of patients are affected, so chloasma is the better answer .Melasma (also known as chloasma faciei, or the mask of pregnancy when present in pregnant women) is a tan or dark skin discoloration. Melasma is thought to be caused by sun exposure, genetic predisposition, hormone changes, and skin irritation. DLE is a benign inflammatory disorder of the skin. Presents with well defined scaly patches which heal with atrophy, scarring, and pigmentary changes. Factors predisposing to DLE: 1.trauma 2.streas 3.UV exposure 4.infection 5.drugs 6.seaonal exacerbations 7.cold exposure Ref: Harrison 20th edition pg 1234', 'role': 'assistant'}]