The Iterated Integral Is

A) $4 \sqrt { 3 }$

Multiple Choice

The iterated integral $\int _ { 0 } ^ { \frac { \pi } { 2 } } \int _ { \frac { \pi } { 6 } } ^ { \frac { \pi } { 2 } } \int _ { 0 } ^ { 2 } \rho ^ { 3 } \sin ( \varphi ) \cos \theta d \rho d \varphi d \theta$ is

A) $4 \sqrt { 3 }$
B) $- 3 \sqrt { 3 }$
C) $3 \sqrt { 3 }$
D) $- 2 \sqrt { 3 }$
E) $2 \sqrt { 3 }$