Which of the following statements are correct?

(A) The M$^{3+}$/M$^{2+}$ reduction potential for iron is greater than manganese.

(B) The higher oxidation states of first row d-block elements get stabilized by oxide ion.

(C) Aqueous solution of Cr$^{2+}$ can liberate hydrogen from dilute acid.

(D) Magnetic moment of V$^{2+}$ is observed between 4.4 - 5.2 BM.

Choose the correct answer from the options given below :

The reduction electrode potential of $\mathrm{Mn}^{3+} / \mathrm{Mn}^{2+}$ is $+1.57 \mathrm{~V}$ while that of $\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}$ is $+0.77 \mathrm{~V}$, hence $\mathrm{A}$ is wrong. Higher oxidation state of smaller $d$-block elements is stabilized (or say form compounds) with smaller anion oxide that can be explained by stearic reason hence $B$ is correct. <br/><br/> The oxidation electrode potential of $\mathrm{Cr}^{2+} / \mathrm{Cr}^{3+}$ is $+0.41 \mathrm{~V}$ hence it can reduce $\mathrm{H}^{+}$and so liberate $\mathrm{H}_2$. The unpaired electrons in $\mathrm{V}^{2+}$ are 3 hence the magnetic moment of $\mathrm{V}^{2+}$ will be lesser than 4.4 BM.<br/><br/> Hence, only $B$ and $C$ are correct.