Let the given equation be,
[tex]^{}f(x)=x^3-x^2-x+1[/tex]
Take the derivative of the function implies,
[tex]f^{\prime}(x)=3x^2-2x-1[/tex]
Put f'(x)=0 gives,
[tex]3x^2-2x-1=0[/tex]
Since, it is a quadratic equation having two roots. Therefore, the number of turning points will be 2.
Hence, Option B.
