B lymphocytes develop immunocompetence in the:

• A. lymph nodes
• B. thymus
• C. spleen
• D. bone marrow

Answer: (D)

Verified step by step guidance

1. Understand the concept of immunocompetence: Immunocompetence refers to the ability of immune cells to recognize and respond to antigens effectively. B lymphocytes are a type of white blood cell involved in the adaptive immune response.
2. Learn about the development of B lymphocytes: B lymphocytes originate and mature in the bone marrow. During their maturation, they acquire immunocompetence, which involves the development of antigen-specific receptors on their surface.
3. Differentiate between primary and secondary lymphoid organs: Primary lymphoid organs, such as the bone marrow and thymus, are where immune cells develop and mature. Secondary lymphoid organs, such as the lymph nodes and spleen, are where mature immune cells interact with antigens and initiate immune responses.
4. Recognize the role of the bone marrow: The bone marrow is the primary site for the development and maturation of B lymphocytes. It provides the necessary environment for these cells to acquire immunocompetence before they migrate to secondary lymphoid organs.
5. Confirm the correct answer: Based on the information above, B lymphocytes develop immunocompetence in the bone marrow, not in the lymph nodes, thymus, or spleen.