Final answer:
The skin is the primary component of the immune system that blocks over 99% of all pathogens. If breached, further innate and adaptive immune responses come into play for defense.
Step-by-step explanation:
The component of the immune system responsible for preventing over 99% of all pathogens from affecting your body is e. The skin. The skin serves as the body's first barrier against pathogens, acting as a mechanical barrier that physically blocks entry of foreign agents.
If pathogens manage to breach these barriers, however, the body has a multi-layered immune system, including the innate immune response involving inflammation and phagocytic cells like macrophages and neutrophils, and the adaptive immune response, which generates a targeted defense against specific pathogens and includes cells like cytotoxic T cells and the production of antibodies.