Find the value of $p\left(x\right)$ for $x=1$ if $p\left(x\right)$ has $(x–1)$ a factor.

The correct option is C: $0$

By Factor theorem, if $(x-a)$ is a factor of polynomial $p\left(x\right),$ then $p\left(a\right)=0$

If $(x-1)$ is a factor of the polynomial $p\left(x\right).$

then, $p\left(1\right)=0$

$\therefore p\left(x\right)=0$ for $x=1$.