Final answer:
B cells mature in the bone marrow and T cells mature in the thymus after initially developing from stem cells in the bone marrow. The correct response to the question about the initial location of B-cell and T-cell development is bone marrow for B cell and thymus for T cell, or option C.
Step-by-step explanation:
The initial location of B-cell and T-cell development is crucial for understanding the adaptive immune response. Both types of lymphocytes originate from hematopoietic stem cells in the bone marrow. For B cells, maturation occurs in the bone marrow itself, which is why they are named B cells for "bone."
On the other hand, after their initial formation in the bone marrow, T cells migrate to the thymus, a primary lymphoid organ, where they mature. Therefore, the correct answer is Bone marrow for B cell and thymus for T cell, which corresponds to option C.