Answer:
True
Step-by-step explanation:
B cells are B lymphocytes and are one of the types of white blood cells. Their main role is in the acquired immune system in which they help in the humoral immune response of the body by the secretion of antibodies. The maturation of the B cells occurs in the bone marrow in mammals. But in birds, these cells mature in an organ named bursa of Fabricius which is a lymphoid organ in birds. These B cells were first isolated form the bursa of Fabricius of the birds.