Three elements X, Y and Z are in the 3rd period of the periodic table. The oxides of X, Y and Z, respectively, are basic, amphoteric and acidic. The correct order of the atomic numbers of X, Y and Z is:

Oxide of x → Basic⇒IA or IIAOxide of y→ amphoteric⇒IIIA Oxide of z→acidic        ⇒IVA or VA or VIA or VIIAAtomic number order is x < y < z (or)As we move across the period, acidic nature of oxides increases.          ∴ x < y < z