Use the Fundamental Identities to Find the Value of the Trigonometric

Use the fundamental identities to find the value of the trigonometric function.
-Find $\tan \theta$ if $\cos \theta = \frac { 1 } { 6 }$ and $\sin \theta < 0$

A) $- \sqrt { 37 }$
B) $- \frac { \sqrt { 35 } } { 35 }$
C) $- \sqrt { 35 }$
D) 6