write -2x^3(4x^3+5x^6) in standard form, classify the degree and find the end behavior.
A) -8x^6-10x^9; 6th degree; up to down.
B) -10x^9-8x^6; 9th degree; up to down.
C) -10x^9-8x^6; 9th degree; down to up.
D) -8x^9-10x^18; 9th degree; up to down.