The oxidation states of nitrogen in NO, NO$$_2$$, N$$_2$$O and NO$$_3^-$$ are in the order of :

To determine the oxidation states of nitrogen in each species, we use the rule that oxygen has an oxidation state of $$-2$$ and the sum of oxidation states equals the overall charge.

In $$\text{NO}$$: $$x + (-2) = 0$$, so $$x = +2$$. In $$\text{NO}_2$$: $$x + 2(-2) = 0$$, so $$x = +4$$. In $$\text{N}_2\text{O}$$: $$2x + (-2) = 0$$, so $$x = +1$$. In $$\text{NO}_3^-$$: $$x + 3(-2) = -1$$, so $$x = +5$$.

Arranging in decreasing order: $$\text{NO}_3^- (+5) > \text{NO}_2 (+4) > \text{NO} (+2) > \text{N}_2\text{O} (+1)$$.

This matches option (1): $$NO_3^- > NO_2 > NO > N_2O$$.