The oxidation state of the central atom in the anion of the compound ${\mathrm{NaH}}_{2}{\mathrm{PO}}_{2}$ will be-

1. +3

2. +5

3. +1

4. -3

Hint: The range of oxidation states shown by  P is -3 to +5

Let the oxidation state of P in ${\mathrm{NaH}}_{2}{\mathrm{PO}}_{2}$ is x.