The correct option is
B Lymph nodes
A lymph node or lymph gland is an ovoid or kidney-shaped organ of the lymphatic system. Humans have approximately 500–600 lymph nodes distributed throughout the body, with clusters found in the underarms, groin, neck, chest, and abdomen. Tonsils are the two lymph nodes located on each side of the back of the throat. Adenoids are a patch of tissue that is located in the roof of the mouth, behind the soft palate where the nose connects to the throat. They, along with the tonsils, are part of the lymphatic system.
So, the correct answer is 'Lymph nodes'.