A nurse is caring for a client who asks about the functions of the thymus, spleen, and lymph nodes. Which of the following responses should the nurse make?

A. The thymus, spleen, and lymph nodes are part of the lymphatic and immune systems and play key roles in immunity by producing and storing immune cells and filtering pathogens. B. These organs do not regulate electrolyte balance; that is primarily the function of the kidneys and endocrine system. C. Digestion is carried out by the gastrointestinal tract, not these organs. D. Vitamin absorption occurs in the small intestine, not the thymus, spleen, or lymph nodes.