Find an Equation in Standard Form for the Hyperbola That $( 0 , \pm 10 )$

Find an equation in standard form for the hyperbola that satisfies the given conditions.
-Foci at $( 0 , \pm 10 )$ , a conjugate axis with length 8

A) $\frac { y ^ { 2 } } { 16 } - \frac { x ^ { 2 } } { 100 } = 1$
B) $\frac { y ^ { 2 } } { 84 } - \frac { x ^ { 2 } } { 16 } = 1$
C) $\frac { y ^ { 2 } } { 100 } - \frac { x ^ { 2 } } { 64 } = 1$
D) $\frac { y ^ { 2 } } { 64 } - \frac { x ^ { 2 } } { 100 } = 1$