Which one of the following set of compounds correctly illustrates the law of reciprocal proportions?

The element O and H combine separately with the third element P to form \(P _2 O _3\) and \(PH _3\) respectively and directly combine to form \(H _2 O\). In \(PH _3, 31\) parts by mass of P combine with 3 parts by mass of H and in \(P _2 O _3, 62\) parts by mass of P combine with 48 parts by mass of O . Thus the masses of H and O which combines with fixed mass of H (say 62 parts by mass) are 6 and 48 and they bear the ratio of \(1: 8\)
Now in \(H _2 O , 2\) parts by mass of H combines with 16 parts by mass of O . So, they combine in ratio \(2: 16\) which is equal to \(1: 8\) which is same as the first ratio.