Find the derivative of the function and simplify your answer.

(x) = 1/x³ + (x) - 5x²

A. none of these
B. ' (x) = 1/3x² + 2/x - 10
C. ' (x) = - 3/x² + 1/x - 10x
D. ' (x) = - 3/x⁴ + 1/x - 10x
E. ' (x) = 4/x⁴ + 2(2x) - 5x²