A metal satisfies all these properties simultaneously

I)  It is tarnished in air reacts with H₂O to from hydroxide and evolves H₂(g)

II)  React with hydrogen at high temp to form metal hydrides

III)  Strong reducing agent

IV)  Dissolve in NH₃ ( liquid) to form a conducting blue solution

The metal may be

Identify the correct statements about alkali metals.

A. The order of standard reduction potential $({\mathrm{M}}^{+} | \mathrm{M})$ for alkali metal ions is $\mathrm{Na} > \mathrm{Rb} > \mathrm{Li}$.

B. $\mathrm{CsI}$ is highly soluble in water.

C. Lithium carbonate is highly stable to heat.

D. Potassium dissolved in concentrated liquid ammonia is blue and paramagnetic.

E. All alkali metal hydrides are ionic solids.

Choose the correct answer from the options given below