This is a basic derivative problem. The first derivative of f(x) would multiply the 7 by the power of x (which is one) and get rid of the 8. So, all you have left is 7 times 1 and your answer would be 7.
The answers is B because you set x+5=0 and x=-5 so that means that the graph needs to be shifted 5 units to the left because 5 is negative and to move 3 units down you just put a -3 at the end of the equation like this y=(x+5)-3