<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 74-year-old man comes to the physician for evaluation of a skin lesion on his right arm. The lesion first appeared 3 months ago and has since been slowly enlarging. Physical examination shows a 1.5-centimeter, faintly erythematous, raised lesion with irregular borders on the dorsum of the right forearm. A biopsy specimen is obtained. If present, which of the following histopathological features would be most consistent with carcinoma in situ?? A: Pleomorphism of cells in the stratum corneum, B: Irreversible nuclear changes in the stratum basale, C: Full-thickness basal to apical cell polarity, D: Increased nuclear to cytoplasmic ratio in the stratum spinosum, E: Presence of epithelial cells in the dermis,  <response>: This is a question about carcinoma in situ in the skin. Carcinoma in situ refers to abnormal cells confined to the epidermis that have not invaded the basement membrane to become an invasive cancer. The key histopathological feature of carcinoma in situ is nuclear changes confined to the lower layers of the epidermis, specifically the stratum basale, without invasion through the basement membrane into the dermis.Pleomorphism in the stratum corneum refers to abnormal cornified layer cells and does not indicate carcinoma in situ. Full thickness cell polarity and increased nuclear to cytoplasmic ratio in stratum spinosum can be seen in reactiveinflammatory conditions and do not indicate carcinoma in situ. Finding epithelial cells in the dermis indicates invasion through the basement membrane, so would not be consistent with carcinoma in situ.B: Irreversible nuclear changes in the stratum basale 