Solve the Equation on the Interval $0 \leq \theta < 2 \pi .$

Multiple Choice

Solve the equation on the interval $0 \leq \theta < 2 \pi .$
- $\cos ^ { 2 } \theta + 2 \cos \theta + 1 = 0$

A) $2 \pi$
B) $\pi$
C) $\frac { \pi } { 4 } , \frac { 7 \pi } { 4 }$
D) $\frac { \pi } { 2 } , \frac { 3 \pi } { 2 }$