<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 76-year-old woman is brought to the physician because of lesions on her left arm. She first noticed them 3 months ago and they have grown larger since that time. She has not had any pain or pruritus in the area. She has a history of invasive ductal carcinoma of the left breast, which was treated with mastectomy and radiation therapy 27 years ago. Since that time, she has had lymphedema of the left arm. Physical examination shows extensive edema of the left arm. There are four coalescing, firm, purple-blue nodules on the left lateral axillary region and swelling of the surrounding skin. Which of the following is the most likely diagnosis?? A: Cellulitis, B: Thrombophlebitis, C: Angiosarcoma, D: Melanoma, E: Kaposi sarcoma,  <response>: This is a clinical case question involving a 76-year-old woman with a history of breast cancer treated with mastectomy and radiation therapy 27 years ago, who now presents with lesions on her left arm in the setting of chronic lymphedema. The key details in the stem are the patients age, history of breast cancer with mastectomy and radiation therapy, chronic lymphedema of the left arm, and the description of the skin lesions as firm, purple-blue nodules in the left axilla. The differential diagnosis includes:- Angiosarcoma: Most likely given her history of radiation therapy for breast cancer and chronic lymphedema, which are risk factors. The lesion description of firm, purple-blue nodules also fits.- Kaposi sarcoma: Less likely as this is associated with immunosuppression. No mention of HIV or immunosuppressive medications. - Melanoma: Unlikely given lesion description and distribution.- Cellulitis and thrombophlebitis: Unlikely as the lesions are described as firm nodules rather than erythema or warmth suggestive of infection.C: Angiosarcoma 