It looks like selections A and C are identical. (Neither is equivalent to 9^x.)
If B is supposed to be 3^(2x), it is equivalent to F and D and to the given expression.
Of course, D evaluates to 9^x, so is equivalent.
Choice E evaluates to 3^(x+2), which is not equivalent to 3^(2x).
The applicable choices appear to be
... B. 3^(2x)
... D. (3*3)^x
... F. (3^x)*(3^x)
