Write the Following as an Algebraic Expression in U, U $\cos ( \arcsin u )$

Write the following as an algebraic expression in u, u > 0.
- $\cos ( \arcsin u )$

A) $\sqrt { u ^ { 2 } + 1 }$

B) $\frac { \sqrt { u ^ { 2 } + 1 } } { u }$

C) $\sqrt { u ^ { 2 } - 1 }$

D) $\sqrt { 1 - \mathrm { u } ^ { 2 } }$