<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 54-year-old woman presents to the emergency department with sudden shortness of breath. A CT scan shows multiple nodules in her left lung. She reports that for the past 6 months, she has been feeling tired and depressed. She also has frequently felt flushed, which she presumed is a symptom of getting closer to menopause. On physical examination, a nodule with a size of 2.5 cm is palpable in the left lobe of the thyroid gland; the nodule is firm and non-tender. Cervical lymphadenopathy is present. Cytology obtained by fine needle aspiration indicates a high likelihood of thyroid carcinoma. Laboratory findings show a serum basal calcitonin of 620 pgmL. A thyroidectomy is performed but the patient presents again to the ER with flushing and diarrhea within 6 weeks. Considering this patient, which of the following treatment options should be pursued?? A: Observation, B: Radioactive iodine radioiodine, C: Thyroid-stimulating hormone TSH suppression, D: Tamoxifen, E: Vandetanib,  <response>: This is a clinical vignette describing a 54-year-old woman with multiple concerning symptoms, including shortness of breath, fatigue, depression, flushing, and a palpable thyroid nodule. She underwent fine needle aspiration of the thyroid nodule, which showed a high likelihood of thyroid carcinoma. She then had a thyroidectomy but presented again soon after with flushing and diarrhea, suggesting persistent disease. The key findings are:- Multiple pulmonary nodules and lymphadenopathy, concerning for metastatic disease- Thyroid nodule suspicious for carcinoma based on FNA - High calcitonin level, specific for medullary thyroid carcinoma- Persistent symptoms after thyroidectomy suggest residual diseaseThis clinical picture is most consistent with metastatic medullary thyroid carcinoma. The treatment options listed include observation, radioactive iodine, TSH suppression, tamoxifen, and vandetanib. Radioactive iodine is used for differentiated thyroid cancers but not medullary carcinoma. TSH suppression may be used as adjuvant therapy but is not definitive treatment. Tamoxifen may be used for palliative purposes in metastatic disease. Vandetanib is a tyrosine kinase inhibitor that targets RET mutations, which are common in medullary thyroid cancer - this would be the most appropriate treatment option for this patient.E: Vandetanib 