Find All Critical Numbers of Of the Function $f ( \theta ) = 2 \sec \theta + \tan \theta , 14 \pi < \theta < 16 \pi .$

Multiple Choice

Find all critical numbers of of the function $f ( \theta ) = 2 \sec \theta + \tan \theta , 14 \pi < \theta < 16 \pi .$

A) $\theta = \frac { 91 \pi } { 6 }$
B) $\theta = \frac { 91 \pi } { 6 } , \frac { 95 \pi } { 6 }$
C) $\theta = \frac { 89 \pi } { 6 } , \frac { 95 \pi } { 6 }$
D) $\theta = \frac { 95 \pi } { 6 }$
E) $\theta = \frac { 31 \pi } { 2 }$