Where do immature lymphocytes differentiate and mature?

Bone marrow and thymus

The correct answer is:

c) Bone marrow and thymus

Immature lymphocytes differentiate and mature in the bone marrow and thymus.

Bone marrow: The bone marrow is the soft tissue found inside the bones. It serves as the primary site of production and maturation for B cells and some types of T cells. In the bone marrow, B cells undergo differentiation and maturation, acquiring antigen receptors and becoming competent to recognize specific antigens.

Thymus: The thymus is a specialized lobed organ located near the heart and beneath the breastbone.
It plays a crucial role in the maturation of T cells. Immature T cells, which are produced in the bone marrow, migrate to the thymus for further development and education. In the thymus, T cells undergo a series of maturation stages and undergo positive and negative selection processes to ensure they recognize antigens appropriately and do not attack the body's own cells.

The spleen and lymph nodes (option a) are secondary lymphoid organs that primarily serve as sites for immune responses and interactions between lymphocytes and antigens. They do not play a direct role in the differentiation and maturation of immature lymphocytes.

The liver and kidneys (option b) are important organs in the body but are not directly involved in the differentiation and maturation of lymphocytes.

Tonsils and appendix (option d) are secondary lymphoid organs that participate in immune responses, particularly in mucosal immune defense. However, they are not the main sites where immature lymphocytes differentiate and mature.