Ans. (a) Nodular sclerosisRef. Robbins pathology 9th ed. /607-610types of Hodgkins lymphomaNodular sclerosisIs the most common subtype and is composed of large tumor nodules showing scattered lacunar classical RS cells set in a background of reactive lymphocytes, eosinophils and plasma cells with varying degrees of collagen fibrosis/sclerosisMixed cellularityMost common format seen in India; also the commonest in HIV positive patients. Biopsy shows classic. Reed Sternberg cells Lymphocyte depletedIs a rare subtype, composed of large numbers of often pleomorphic RS cells with only a few reactive lymphocytes which may easily be confused with diffuse large cell lymphoma. Many cases previously classified within this category would now be reclassified under anaplastic large cell lymphomaLymphocyte-richGood/best prognosisNodular lymphocytic predominantExpresses CD20 and is classified as considered a form of non- classical Hodgkin's.*Microscopic examination of the lymph node biopsy reveals complete or partial effacement of the lymph node architecture by scattered large malignant cells known as Reed-Sternberg cells (RSC) admixed within a reactive cell infiltrate composed of variable proportions of lymphocytes, histiocytes, eosinophils, and plasma cells.*The Reed-Sternberg cells are identified as large often bi-nucleated cells with prominent nucleoli and an unusual CD45-, CD30+, CD 15+/- immunophenotype. In approximately 50% of cases, the Reed-Sternberg cells are infected by the Epstein-Barr virus.*Characteristics of classic Reed-Sternberg cells include large size (20-50 micrometers), abundant, amphophilic, finely granular/homogeneous cytoplasm; two mirror- image nuclei (owl eyes) each with an eosinophilic nucleolus and a thick nuclear membrane (chromatin is distributed close to the nuclear membrane).