This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Skin
[{'content': 'Xeroderma pigmentosum is caused due to: \nSelect and explain. \nA. DNA synthesis defect, B. Ectodermal cell migration defect, C. Abnormal nucleotide excision repair, D. Melanocyte proliferation', 'role': 'user'}, {'content': "Answer: C \nExplanation: Xeroderma pigmentosum (XP) is a rare autosomal recessive disease characterized by photosensitivity, pigmentary changes, premature skin ageing, neoplasia and abnormal Nucleotide excision repair. Ref: Rook's textbook of dermatology, 8th edition, Pg15.71.", 'role': 'assistant'}]