Its given that WA = NO and AS = OT
The angle between WA and AS is A.
The angle between NO and OT is O.
Since WA = NO and NO = OT, A and O are corresponding angles.
But, from the given data, A = O.
Therefore, two pairs of sides and their included angles are equal.
So, the congruence that supports the conclusion is SAS (SIDE-ANGLE-SIDE).