If ∠O≅∠P

To use the AAS (Angle-Angle-Side) Congruence Theorem to prove that ΔNOR ≅ ΔQPR, we already have two pairs of angles that are congruent:

1. ∠O ≅ ∠P
2. ∠R ≅ ∠R (by the Reflexive Property)

According to the AAS theorem, we need an additional set of congruent sides that is between the two angles we already have.

Therefore, the additional information needed should be a congruence between the sides opposite to one of the angles we have already established (∠O or ∠P) and the other angle (∠R).

Looking at the choices:

1) NO̅̅̅̅̅̅≅QP̅̅̅̅̅̅ — This could be useful, but it does not correspond with the AAS requirement related to the angles we've identified.

2) NO̅̅̅̅̅̅≅PR̅̅̅̅̅̅ — This also doesn't connect directly with our requirements as it mixes the labels with no direct connection to the angle at R.

3) OR̅̅̅̅̅̅≅PR̅̅̅̅̅̅ — This could help if congruence is established relating R with the triangle based on two known angles.

4) NR̅̅̅̅̅̅≅QP̅̅̅̅̅̅ — Again, this does not relate appropriately to the AAS requirement given our established angles.

The best option in terms of providing congruence related to our established angles and the AAS (where the side needs to be opposite one of the given angles) is actually:

**3) OR̅̅̅̅̅̅≅PR̅̅̅̅̅̅**.

This would confirm the third necessary element to establish ΔNOR ≅ ΔQPR by AAS.