Answer:
Answer is B. Only available in the blood during response to pathogen.
Explanation:
Complements are part of the immune system which contains series proteins, interacting together, thereby enhancing the ability of the antibodies to eliminate pathogens.
Functions of complements can be broken into four, these are
* Lysis of pathogens
*Inflammation activation
* Enhance phagocytosis of antigens
* Clearance of the immune system.
