In which of the following transition metal ion (aquated) is not correctly matched with its colour?

Consider the following pairs of elements and identify the pairs of elements which have nearly same atomic radius.

I. Y, La

II. Zr, Hf

III. Mo, W

IV. Cr, Mo

$E_{\mathrm{M}^{3}| \mathrm{M}^{2+}}^{\circ}($ in V$)$ is highest for

Identify the correct statements about lanthanoids

I. $\mathrm{Ce}^{4+}$ and $\mathrm{Tb}^{4+}$ act as oxidising agents.

II. $\mathrm{Eu}^{2+}$ and $\mathrm{Yb}^{2+}$ act as oxidising agents.

III. Misch metal is an alloy of $95 \%$ iron and $5 \%$ lanthanoid metal.

IV. $\mathrm{La}^{3+}$ and $\mathrm{Ce}^{4+}$ are diamagnetic in nature.