Answer:
B. Natural Selection, others are some what related to genetic engineering.
Answer:
The correct answer a. Normal microbiota may significantly impact human health and disease.
Explanation:
Even though many organs and body parts of humans are properly working with the presence of microorganisms, when the population exceeds certain limits, the effect can be opposite and bad for health.
Well If the Salmon die from lack of food from polution or something, and other animals benafit from the nutrience they carry. the rest of the ecosystem might parish, i hope that helped im not sure what was wanted
