Use the Trigonometric Substitution to Rewrite the Algebraic Expression as a Trigonometric

Multiple Choice

Use the trigonometric substitution to rewrite the algebraic expression as a trigonometric function of θ,where $0 < x < \frac { \pi } { 2 }$ . $\sqrt { x ^ { 2 } - 16 } , x = 4 \sec \theta$ ​

A) 4 tan θ
B) 16 sec θ
C) - 4 tan θ
D) 4 sec θ
E) 16 tan θ