If a magnetic material is having magnetic susceptibility $(\chi )=-1$, then the relative magnetic permeability $({\mu }_r)$ and type of magnetic material is?

Here, $\chi =-1$
then ${\mu }_r=1+\chi \Rightarrow {\mu }_r=1+(-1)=I-1=0$
Since, magnetic susceptibility of given material is less than one. Hence, the given magnetic material is a diamagnetic material.