The side length, s, of a cube is 4x^2+3. If V=s^3, what is the volume of the cube?

A.) 64x^6+144x^4+108x^2+27
B.) 64x^6+48x^4+12x^2+1
C.) 4x^6+36x^4+108x^2+27
D.) 4x^6+12x^4+12x^2+1