Which statements are correct for silicon?

I.     Its electron arrangement is 2,8,4.

II.     It has four electrons in its highest occupied energy level.

III.     In the solid state, each silicon atom is covalently bonded to four other silicon atoms in a tetrahedral arrangement.

A.     I and II only

B.     I and III only

C.     II and III only

D.     I, II and III

D