Answer
$\text{(a) F}\\
\text{(b) H}\\
\text{(c) G}\\
\text{(d) C}$
Work Step by Step
(a) $(-3x)^{1/3}$
$x^{y/z}$ can be rewritten as $\sqrt[z] {x^y}$.
$(-3x)^{1/3} = \sqrt [3] {-3x}$
(b) $(-3x)^{-1/3}$
$x^{-y/z}$ can be rewritten as $\frac{1}{\sqrt[z] {x^y}}$.
$(-3x)^{-1/3} = \frac{1}{\sqrt [3] {-3x}}$
(c) $(3x)^{1/3}$
$x^{y/z}$ can be rewritten as $\sqrt[z] {x^y}$.
$(3x)^{1/3} = \sqrt [3] {3x}$
(d) $(3x)^{-1/3}$
$x^{-y/z}$ can be rewritten as $\frac{1}{\sqrt[z] {x^y}}$.
$(3x)^{-1/3} = \frac{1}{\sqrt [3] {3x}}$