The side length, s, of a cube is 4x² + 3. If V = s3, what is the volume of the cube?

A. 64x⁶ + 144x⁴ + 108x² + 27
B. 64x⁶ + 48x⁴ + 12x² + 1
C. 4x⁶ + 36x⁴ + 108x² + 27
D. 4x⁶ + 12x⁴ +12x² + 1