Answer: Choice C. g(x) = (x-4)^2
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Explanation:
If we were to keep the red curve completely fixed, but we moved the xy axis four units to the left, then this would give the illusion the red curve is moving four units to the right to arrive at the blue curve's location.
Shifting the xy axis four units to the left is the same as subtracting 4 from each initial input x value. So we go from x to x-4.
The parent function f(x) = x^2 then becomes g(x) = (x-4)^2 which is choice C.
As one way to check, plug in x = 4 and you should find that g(4) = 0. This is the x intercept of the blue curve. Something like g(x) = (x+4)^2 does not work because plugging x = 4 into this leads to g(x) = 64, so that rules out choice A. You can eliminate choices B and D for similar reasoning as well.
