the electronic configuration of four elements lq

Question

The electronic configuration of four elements L,Q, P, and R are given in brackets:

L ( 1s² , 2s², 2p⁴)        Q (1s² , 2s², 2p⁶, 3s² ,3p⁵)
P ( 1s² , 2s² 2p⁶, 3s¹)  R ( 2s² ,  2s², 2p⁶ , 3s²,)

The formulae of ionic compounds that can be formed between these elements are:

(1)  L,P, RL, AND R₂ Q

(2)  LP, RL, PQ, AND RQ

(3)  P₂ , RL, PO and  RQ₂

(4) LP,  R₂L, P₂ and RQ

Ans:   P₂ , RL, PO and  RQ₂