<prompt> Sections from a solid-cystic unilateral ovarian tumor in a 30-year old female show a tumor composed of diffuse sheets of small cells with doubtful nuclear grooving and scanty cytoplasm. No Call-Exner bodies are seen.The ideal immunohistochemistry panel would include -Vimentin, epithelial membrane antigen, inhibin, CD99Desmin, S-100 protein, smooth muscle antigen, cytokeratinChromogranin, CD45, CD99, CD20CD3, chromagranin, CD 45, synaptophysin  <response>: Ans. is a i.e., Vimentin, epithelial membrane antigen, inhibin, CD99This patient is having granulosa cell tumor of ovary which is chracterized histologically by :i Diffuse sheets of round and oval cells ii Inconspicuous groove and folds in nuclei - coffee bean appearanceiii Scant cytoplasmo Granulosa cell tumor is positive for -- i Vimentin, ii Inhibin, iii CD99o Epithelial membrane antigen is positive in surface epithelial tumor.So, a option a is the best, and markers given in this option will help to make the diagnosis of granulosa cell tumor. 