Final answer:
The statement D: f(x) is an odd function for all odd values of m is true.
Step-by-step explanation:
An even function is symmetric about the y-axis, while an odd function is generated by reflecting the function about the y-axis and then about the x-axis. When we have the function f(x) = (xm + 9)^2, the exponent, m, determines whether the function is even or odd. If m is an even number, f(x) will be an even function. If m is an odd number, f(x) will be an odd function. Therefore, statement D: f(x) is an odd function for all odd values of m is true.