<prompt> Which of the following is seen on electron microscopy of medullary thyroid carcinoma specimens?Presence of electron-dense granules in the nucleusPresence of electron-dense granules in the mitochondriaPresence of electron-dense granules in the endoplasmic reticulumPresence of electron-dense granules in the cytoplasm  <response>: Medullary carcinoma on electron microscopy reveals variable numbers of membrane-bound electron-dense granules within cytoplasm of neoplastic cells. 