Find a Polar Equation of the Conic with Its Focus $e = 1$

Multiple Choice

Find a polar equation of the conic with its focus at the pole. ​
Conics
Eccentrity
Directrix
Parabola $e = 1$ $y = - 2$ ​
​

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