Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : In aqueous solutions $\mathrm{Cr}^{2+}$ is reducing while $\mathrm{Mn}^{3+}$ is oxidising in nature.

Reason (R) : Extra stability to half filled electronic configuration is observed than incompletely filled electronic configuration.

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

Choose the correct statements from the following

A. $$\mathrm{Mn}_2 \mathrm{O}_7$$ is an oil at room temperature

B. $$\mathrm{V}_2 \mathrm{O}_4$$ reacts with acid to give $$\mathrm{VO}_2{ }^{2+}$$

C. $$\mathrm{CrO}$$ is a basic oxide

D. $$\mathrm{V}_2 \mathrm{O}_5$$ does not react with acid

Choose the correct answer from the options given below :

Identify correct statements from below:

A. The chromate ion is square planar.

B. Dichromates are generally prepared from chromates.

C. The green manganate ion is diamagnetic.

D. Dark green coloured $$\mathrm{K}_2 \mathrm{MnO}_4$$ disproportionates in a neutral or acidic medium to give permanganate.

E. With increasing oxidation number of transition metal, ionic character of the oxides decreases.

Choose the correct answer from the options given below:

The metals that are employed in the battery industries are

A. $$\mathrm{Fe}$$

B. $$\mathrm{Mn}$$

C. $$\mathrm{Ni}$$

D. $$\mathrm{Cr}$$

E. $$\mathrm{Cd}$$

Choose the correct answer from the options given below: