Final answer:
Tonsils are composed of lymphatic tissue and help fight infection by trapping bacteria.
Step-by-step explanation:
The answer to the question is Tonsils (option A).
Tonsils are composed of lymphatic tissue and are located in the throat. They act as a defense mechanism by trapping bacteria and helping to fight infection. Lymphocytes in the tonsils destroy the trapped pathogens, preventing them from causing further harm to the body.