First distribute the exponent (1/3) to both inner terms. Keep in mind that the exponents are multiplied by each other. For example: (x^a)^b = x^(a*b)....an exponent rule

=8^(1/3) * x^{-6*(1/3)}

Cubed root of 8 is 2. (2^3=8). (-6*1)/3=-2

=2*x^-2

A negative exponent can be expressed as a positive exponent in the denominator:

=2/x^2

2/(x^2)

Answer is D.

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