Correct Answer - D Ans. D. DNA repair defect [Ref Rooks 4thie p. 78.12] Xeroderma pigmentosa Molecular defect: Exposure to UV rays damages DNA due to production of convalent linkages between adjacent pyrimidines (pyrimidine dimmers). Normally the damaged DNA is repaired by excision and repair. In xeroderma pigmentosa the repair of UV damaged DNA is defective. It is an autosomal recessive disorder. @dermatology_vid 11.3K views10:59
