Which shows one way to determine the factors of x^3 + 4x2 + 5x +20 by grouping?
A. x(x^2+4) + 5(x^2+4)
B. X^2(x+4) +5(x+4)
C. x^2(x+5) +4(x+5)
D. x(x^2+5) + 4x(x^2+5)