All are peripheral lymphoid organs except -: (A) Lymph nodes, (B) Spleen, (C) Mucosa associated lymphoid tissue, (D) Thymus
Answer is D. Thymus & bone marrow are primary/central lymphoid organ, the spleen & lymph nodes are the secondary/peripheral lymphoid organ Reff: Ananthanarayanan & Paniker's textbook of microbiology 9th edition pg: 128