Find All Real Values Of $x$ Such That $f ( x ) = 0$

Multiple Choice

Find all real values of $x$ such that $f ( x ) = 0$ .
$$f ( x ) = 49 x ^ { 2 } - 64$$

A) $\pm \frac { 7 } { 8 }$

B) $\pm \frac { 8 } { 7 }$

C) $\pm \frac { 64 } { 49 }$

D) $- \frac { 64 } { 49 }$

E) $\frac { 8 } { 7 }$