The lymph nodes in the knee are called the:

A. Species specific immunity refers to the natural resistance that a species has to certain diseases that affect other species. This type of immunity prevents humans from contracting certain diseases that are specific to other animals, like certain viruses or bacteria.
B. Specific immunity refers to the adaptive immune response that targets particular pathogens, but it doesn't apply to the protection humans have against animal-specific diseases.
C. Nonspecific immunity refers to the general defense mechanisms (like skin or phagocytes) that protect the body from a broad range of pathogens, not specifically from animal diseases.
D. Active immunity involves the body producing its own immune response after exposure to a pathogen, but it does not specifically describe the protection from diseases of other

A. Interferon is a type of protein produced by the body in response to infections, particularly viral infections. It is not related to allergens.
B. Macrophage is a type of white blood cell that engulfs and digests pathogens, dead cells, and other debris. It is not an allergen.
C. An allergen is a substance that triggers an allergic reaction. It is considered a type of antigen—a foreign substance that the immune system recognizes and reacts to, often causing symptoms like inflammation, swelling, or itching in allergic individuals.
D. Antibody is a protein produced by B cells that binds to specific antigens, but it is not an allergen.