Find a Polar Equation of the Conic with Its Focus $\quad$

Multiple Choice

Find a polar equation of the conic with its focus at the pole.
Conics $\quad$$\quad$$\quad$ Vertex or vertices
Parabola $\quad$$\quad ( 1 , - \pi / 2 )$

A) $\frac { 2 } { 1 - \cos \theta }$
B) $\frac { 2 } { 1 + \cos \theta }$
C) $\frac { - 2 } { 1 - \sin \theta }$
D) $\frac { 2 } { 1 - \sin \theta }$
E) $\frac { 2 } { 1 + \sin \theta }$