The correct option is A A - Valves, B - Capsule, C - Efferent vessel, D - Immune cells, E - Cortex, F - Afferent vessel
Lymph nodes are very important parts of the immune system, harbouring many immune cells that clear pathogens which drain in along with the lymph. The outermost covering of the lymph node is a tough layer called the capsule. The capsule has extensions which divide the cortex into many compartments. There are many afferent vessels that bring lymph into the lymph nodes. Valves present in the afferent vessels prevent lymph from flowing back. As the lymph reaches the lymph nodes carrying pathogens and cell debri, they are cleared by macrophages and other immune cells present in the lymph node. The lymph, free of all pathogens, is returned to circulation via the efferent lymph vessel.