If the form of the solution of the differential equation $\left(y^3+x\right) \frac{d y}{d x}=y$ when $y(4)=2$ is $y^3=a x+b$, then $4 a+12 b^2=$

• A

  2
• B

  4
• Correct answer
  C

  8
• D

  16

Hence, the correct answer is option: 'C'.