Find the Exact Value of the Expression $\csc 240 ^ { \circ }$

Multiple Choice

Find the exact value of the expression.
- $\csc 240 ^ { \circ }$

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