Correct Answer – 3
As we move down the group the acidic character of oxides ( in a given oxidation state)decreases .Thus `P` oxides are more acidic than `As` oxide for different oxides of the same element ,the acidic character increase as the oxidation number of the central atom increase. Thsu the correct order of acidic character is
`overset(+5)(P_(4))O_(10) gt overset(+3)(P_(4))O_(6) gt overset(+5)(As_(4))O_(10) gt overset(+3)(As_(4))O_(6)`