Assuming) x is negative (makes it easier)

(-2)(-2^2)(-2^3)

(-2)^3.(-2)^3

The two negative numbers will remain negative, so they will both cancel out.

So we need an equation where x^n with n being odd.

a) not sufficient -> will always be positive

b) not sufficient -> equals x^4 which will always be positive

c) not sufficient -> equals x^2 which will always be positive

d) -2+-8 = -10!!!

e) 3*4=12 is positive (pemdas!)

Answer is d

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Took the Gmat and got a 520 after studying for 3 weeks with a fulltime job. Now taking it again, but with 6 weeks of prep time and a part time job. Studying every day is key, try to do at least 5 exercises a day.