When you expand the binomial, you isolate each of the parts. So, (x-y)^4 would turn into...
x^4 - y^4
The powers stay the same because (outside the parenthesis) you multiply them with whatever is inside the parenthesis. In this case, would be 1. All variables and numbers without a listed power have a power of one. Multiply 4*1 to get 4.
Probally d most likely because if you know what the deer looks like it is orange and white spots so it is more manipulating the light from the leaves. If im wrong then its A