Why Do Lymph Nodes Often Become Swollen During an Infection

Why do lymph nodes often become swollen during an infection?

A) T cells reproduce in lymph nodes after being exposed to pathogens.
B) B cells reproduce in lymph nodes after being exposed to pathogens.
C) Macrophages move to lymph nodes after engulfing pathogens.
D) Cytotoxic T cells attack pathogens in the lymph nodes, triggering inflammation.
E) Vasodilation increases blood flow in the lymph nodes.