This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Biology, Subject name: Biochemistry
All of the following disorders are due to defective nucleotide excision repair, EXCEPT 
Select and explain. 
A. Xeroderma pigmentosum, B. Cockayne syndrome, C. Trichothiodystrophy, D. Hereditary nonpolyposis colon cancer
D: Hereditary nonpolyposis colon cancer
Answer: D: Hereditary nonpolyposis colon cancer 
Explanation: Disorders of nucleotide repair Defective nucleotide excision repair Xeroderma pigmentosum Cockayne syndrome Trichothiodystrophy Defective mismatch repair Hereditary nonpolyposis colorectal cancer (HNPCC) Defective non homologous end joining repair Severe combined immunodeficiency disease (SCID)