Answer:
The correct answer is option A.
Explanation:
The lymph node is a small bean-like structure that filters substances that move through the lymphatic pathway with the lymphatic fluid. Lymph nodes are present on different site in the human body. They contain white blood cells that soldiers of the human immune system and fight with infection and pathogens.
Immune system cell that is B and T cells both, not just located in the cortex only but medulla of lymph nodes.
Thus, the correct answer is option A.
