Help me please! Please give me an explanation!

The answer is D

Step-by-step explanation:

Another way to write your question would be: How is the graph of f(x)=x^2 transformed to create the graph g(x)= x^2 - 9.

When ever you subtract form a graph you are going are moving that amount down.

Example: g(x) = x^2 - 2 is equal to f(x) = x^2 moved down 2 units.

When ever you add to a graph you are going are moving that amount up.

Example: g(x) = x^2 + 4 is equal to f(x) = x^2 moved up 4 units.

When ever you subtract in parentheses in a graph you are moving that amount right.

Example: g(x) = (x - 5)^2 is equal to f(x) = x^2 moved right 2 units.

When ever you add in parentheses in a graph you are moving that amount left.

Example: g(x) = (x + 7)^2 is equal to f(x) = x^2 moved left 7 units.

Hope this helps! :)