Answer: b) angle OPN and angle TSU
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Explanation:
Each answer choice involves angle OPN, so the other angle must be based off this. The other angle is TSU because these two angles are on alternating sides of the transversal line UN.
Angle OPN and angle TSU are also exterior angles because they are on the outside region of the parallel lines OQ and RT.
So combine the two concepts and we can say that angles OPN and TSU are alternate exterior angles. The other alternate exterior angle pair is angle USR and angle NPQ.
Due to the parallel lines, the alternate exterior angles are congruent.