T cell-dependent region is -: (A) Cortical follicles of lymph node, (B) Medullary cords, (C) Mantle layer, (D) paracortical area
Answer is D. Periarterial lymphoid tissues

Thymus-dependent (T cells collection)

1. Spleen
    - Periarterial lymphoid collection
    - Malphigian corpuscle in the white pulp
2. Lymph node
           - Paracortical area

Thymus-independent (B cells collection)

1. Spleen
           - Perifollicular region
           - Mantel layer
2. Lymph node
           - Cortical follicles
           - Germinal centres
           - Medullary cords