Which of the Following Functions Is Represented by the Graph $y = \frac { 1 } { 3 } \csc \frac { \pi x } { 2 }$

Multiple Choice

Which of the following functions is represented by the graph below?

A) ​ $y = \frac { 1 } { 3 } \csc \frac { \pi x } { 2 }$
B) ​ $y = \frac { 1 } { 3 } \tan \frac { \pi x } { 2 }$
C) ​ $y = \cot ( x + \pi )$
D) ​ $y = \frac { 1 } { 3 } \csc \pi x$
E) ​ $y = \sec \left( \frac { x } { 3 } \right)$