B. Spinal nerves I think, it makes most sense to me.
Answer:
antibodies
Explanation:
The third line of defense is specific resistance. This system relies on antigens, which are specific substances found in foreign microbes. Most antigens are proteins that serve as the stimulus to produce an immune response. The term "antigen" comes from ANTI-body GENerating substances.
Answer:
Environment affects animal behavior by changing the availability of survival resources like food & shelter, as well as situational things like proximity to human activity. Sometimes the same species of animal will behave completely differently in a forest environment compared to an urban environment.
Explanation:
1. Vocational
2. physical
3. Social
