If you don’t know for sure don’t answer this is a test and I don’t wanna get it wrong :)
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3^3 = 27, so 3 is a good value.
(-3)^3 = -27, not it's not -3
9^3 = 729, so 9 is not good.
(-9)^3 = -729, so -9 is not good.
The answer is A) x=3.