Humans might need to change location to live because their will be increased direct Sunray which of course very harmful to humans A is the answer
They both, I guess you could say, interact with each other. If we didn't have gravity, we wouldn't have air pressure.
No, some animals (at the bottom of the food chain) suffer according to natural selection while other animals who are stronger (likely predators) Will succeed more and have a better chance of survival
In that case the answer is: water, carbon dioxide, and light energy (photons).
It's C because their will be a higher risk that the genetic material of blindness will most likely past to the child.