f(x)=3x^3-2x^2+4x-5
g(x)=6x-7

find (f+g)(x)

A. (f+g)(x)=3x^3-2x^2+10x-12
B.(f+g)(x)=3x^3-2x^2+10x+12
C.(f+g)(x)=3x^3-2x^2-2x+12
D.(f+g)(x)=3x^3-2x^2-2x-2