Solve the Inequality $x ^ { 3 } - 3 x ^ { 2 } - 6 x + 8 \geq 0$

Multiple Choice

Solve the inequality. Write the solution set in interval notation.
- $x ^ { 3 } - 3 x ^ { 2 } - 6 x + 8 \geq 0$

A) $( - \infty , - 2 ] \cup [ 1,4 ]$
B) $( - \infty , - 2 ] \cup [ 4 , \infty )$
C) $[ - 2,1 ] \cup [ 4 , \infty )$
D) $[ - 4 , - 1 ] \cup [ 2 , \infty )$