Assume That $\theta$ Is an Acute Angle in a Right Triangle Satisfying the a Right

Multiple Choice

Assume that $\theta$ is an acute angle in a right triangle satisfying the given conditions. Evaluate the indicated trigonometric
function.
- $\csc \theta = \frac { 5 } { 2 } ; \cos \theta$

A) $\frac { \sqrt { 21 } } { 5 }$
B) $\frac { 2 } { 5 }$
C) $\frac { 2 } { \sqrt { 21 } }$
D) $\frac { \sqrt { 21 } } { 2 }$