Parrom connected on five 3-pointers and hauled down seven rebounds for the Wildcats (23-4, 11-4 Pac-12), who reeled off their third straight victory.
Mark Lyons contributed 14 points and Kaleb Tarczewski had 12 points and six rebounds for Arizona.
Brock Motum paced the Cougars (11-17, 2-13) with 20 points.
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