Find an Equation of Variation in Which the Following Are $y$

Multiple Choice

Find an equation of variation in which the following are true.
- $y$ varies jointly as $x$ and $w$ and inversely as $z$ , and $y = \frac { 9 } { 2 }$ when $x = 2 , w = 6$ , and $z = 24$ .

A) $y = \frac { 6 z } { x w }$
B) $y = 4 x w z$
C) $y = \frac { 6 x w } { z ^ { 2 } }$
D) $y = \frac { 9 x w } { z }$