This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid Tumor, Subject name: Pathology
A palpable mass is noted in the right lobe of the thyroid of a 45-year-old man who visits his physician for a periodic checkup. A biopsy is performed and results in a diagnosis of medullary carcinoma of the thyroid. Which of the following histologic features of thyroid disease would most likely be present in this biopsy specimen? 
Select and explain. 
A. Tumor cells with "Orphan Annie" nuclei, B. Psammoma bodies, C. Tumor cells embedded in an amyloid-laden stroma, D. Infiltrates of lymphocytes with germinal center formation
C: Tumor cells embedded in an amyloid-laden stroma
Answer: C: Tumor cells embedded in an amyloid-laden stroma 
Explanation: - Medullary carcinoma of thyroid is a calcitonin-producing tumor of C cells of thyroid contributing to amyloid deposition within tumor. OTHER OPTIONS GIVEN: - Tumor cells with "Orphan Annie" nuclei & presence of psammoma bodies are seen in papillary carcinoma of thyroid. - Infiltrates of lymphocytes with germinal center formation are seen in Hashimoto thyroiditis.