The answer your looking for is adaptation. I would know, for I just recently finished a chapter on it.
D. A deceased family member
The lymphatic system includes areas of high concentrations of APCs, T and B cells.
<h3>What is the lymphatic system?</h3>
The lymphatic system is a branch of the circulatory system which consists of a system of organs , tissues, cells and vessels known as lymphatic vessels, which help transport the fluid, lymph around the body.
The lymphatic system contains high concentration of immune cells.
Therefore, the lymphatic system includes areas of high concentrations of APCs, T and B cells.
Learn more about lymphatic system at: brainly.com/question/3318384
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