Derivative of x3 + 1 with respect to x2 + 1 is

$z = x^3+1$        $y = x^2+1$

$\frac{dz}{dx} = 3x^2$          $\frac{dy}{dx} = 2x$

so  $\frac{dz/dx}{dy/dx} = \frac{dz}{dy} = \frac{3x^2}{2x}$

so  $\frac{d(x^3+1)}{d(x^2+1)} =\frac{3x}{2} $

Option: 4