Solve the Problem $\theta ( 0 \leq \theta < 2 \pi )$

Solve the problem.
-For what values of $\theta ( 0 \leq \theta < 2 \pi )$ do maximum r-values occur on the graph of the polar equation $r = 2$ cos Note that a maximum $\mathrm { r }$ -value occurs at a point that is the maximum distance from the pole.

A) $0 , \frac { \pi } { 2 } , \pi , \frac { 3 \pi } { 2 }$
B) $\frac { \pi } { 8 } , \frac { 3 \pi } { 8 } , \frac { 5 \pi } { 8 } , \frac { 7 \pi } { 8 } , \frac { 9 \pi } { 8 } , \frac { 11 \pi } { 8 } , \frac { 13 \pi } { 8 } , \frac { 15 \pi } { 8 }$
C) $0 , \frac { \pi } { 4 } , \frac { \pi } { 2 } , \frac { 3 \pi } { 4 } , \pi , \frac { 5 \pi } { 4 } , \frac { 3 \pi } { 2 } , \frac { 7 \pi } { 4 }$
D) $\frac { \pi } { 8 } , \frac { 5 \pi } { 8 } , \frac { 9 \pi } { 8 } , \frac { 13 \pi } { 8 }$ ?