Answer: Choice C. g(x) = (3x)^2
To confirm this, plug in x = 1 and you'll find that:
g(x) = (3x)^2
g(1) = (3*1)^2
g(1) = (3)^2
g(1) = 3*3
g(1) = 9
Showing that (1,9) is on the red g(x) curve.
