I need help with a Algebra question. All explanations and answers will be used to help me learn.

Simplify the expression below. Assume all variables are nonnegative real numbers.:

fourth root of negative 256 x to the power of 8 end root

A. -4x2

B. 4 open vertical bar x squared close vertical bar

C. -4x2, 4x2

D. no real answer