Select the correct statement about lymphocytes.
(a) b cells produce plasma cells, which secrete antibodies into the blood.
(b) the two main types are t cells and macrophages.
(c) t cells are the precursors of b cells.
(d) t cells are the only form of lymphocyte found in lymphoid tissue.

(A) B cells produce plasma cells, which secrete antibodies into the blood.

Explanation:

Lymphocytes are one of several types of defense cells in the body and belong to a group of cells called leukocytes or white blood cells. These cells are produced in the bone marrow and defend the body against disease, infection or allergies. Lymphocytes, in particular, are usually increased when there is an infection and their amount serves as an indicator for various diseases such as influenza, allergy, toxoplasmosis, rubella, leukemia and even HIV.

There are several types of lymphocytes in the human body. Antibodies are produced by B cells (also called B lymphocytes) and have the ability to specifically combine with foreign substances in the body, inactivating them. Antigens are extremely specific, so we can say that for each of its types there is a type of antibody, complementary to that of the antigen.