The indented area of the lymph node where efferent lymphatic vessels exit is called the

A. Neutrophils are a type of white blood cell that primarily responds to bacterial infections and perform phagocytosis, not specifically attacking tumor or virus-infected cells.
B. Regulatory T cells help regulate the immune response and prevent excessive immune activity, but they do not directly attack tumor or virus-infected cells.
C. Natural killer (NK) cells are a type of lymphocyte that plays a key role in the body's defense against tumor cells and virus-infected cells by directly attacking and destroying them.
D. Memory T cells are responsible for "remembering" a previous pathogen, enabling a quicker response upon future exposure, but they do not directly attack tumor or virus-infected cells.

A. Lacteals are specialized lymphatic capillaries located in the villi of the small intestine. They absorb digested fats (in the form of chylomicrons) and transport them into the lymphatic system, eventually entering the bloodstream.
B. Peyer patches are clusters of lymphoid tissue found in the small intestine, important for immune surveillance, but they are not involved in fat absorption.
C. Kupffer cells are specialized macrophages in the liver that filter blood, not involved in lymphatic fat transport.
D. Lymph capillaries generally collect interstitial fluid to form lymph, but lacteals are the specific type of lymph capillary responsible for absorbing dietary fats.