Your answer is most likely C
Answer:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. The skin, nails and hair form the integumentary system, which stops dirt and pathogens from entering the body.
I'm pretty sure it's Cell membrane
Answer:
It would have to be passive immunity
Explanation:
Because active immunity develops after being exposed to the pathogen and its not acquired either because its similar to active and it isn't inborn because that comes from your parents
