$\int \frac{x^4+x^2+1}{x^2-x+1} \,d x$ is equal to

• A
  $\frac{x^3}{3}-\frac{x^2}{2}+x+c$,(where $c$ is a constant of integration)
• B
  $\frac{x^3}{3}+\frac{x^2}{2}+x+c$,(where $c$ is a constant of integration)
• C
  $\frac{x^3}{3}-\frac{x^2}{2}-x+c$,(where $c$ is a constant of integration)
• D
  $\frac{x^3}{3}+\frac{x^2}{2}-x+c$,(where $c$ is a constant of integration)