If A=6x^3-x^2+4x+8 and B= 2x^3+x-5 then A-B equals

A) 4x^3-x^2+3x-13
B) 8x^3-x^2+5x+3
C) 4x^3-x^2+3x+13
D) 8x^3+3x+3


Please answer ASAP!! No jokes please.