Solve the Problem $8 x ^ { 3 } - 42 x ^ { 2 } + 43 x - 12 = 0$

Multiple Choice

Solve the problem.
-Solve the equation $8 x ^ { 3 } - 42 x ^ { 2 } + 43 x - 12 = 0$ given that $\frac { 1 } { 2 }$ is a root.

A) $\left\{ \frac { 1 } { 2 } , \frac { 3 } { 4 } , 4 \right\}$
B) $\left\{ \frac { 1 } { 2 } , - \frac { 3 } { 4 } , - 4 \right\}$
C) $\left\{ \frac { 1 } { 2 } , 1,3 \right\}$
D) $\left\{ \frac { 1 } { 2 } , - 1 , - 3 \right\}$