Although +3 oxidation state is most common in lanthanoids, cerium still shows +4 oxidation state because:

The calculated 'spin-only' magnetic moment $\mathrm{Ti}^{2+}\left(3 \mathrm{~d}^2\right)$ is :

Match List - I with List - II.

Choose the correct answer from the options given below :

Given below are two statements :

Statement I: Ferromagnetism is considered as an extreme form of paramagnetism.

Statement II : The number of unpaired electrons in a $\mathrm{Cr}^{2+}$ ion $(\mathrm{Z}=24)$ is the same as that of a $\mathrm{Nd}^{3+}$ ion $(\mathrm{Z}=60)$.

In the light of the above statements, choose the correct answer from the options given below :