2015 was a great year for pop music, especially for true lovers of girl groups.

The year was book-ended by two major pop releases by arguably the two biggest girl groups out there right now: Fifth Harmony's Reflection, released on January 30, and Little Mix's Get Weird, which just dropped last week on November 6.

5H's long-awaited debut provided finger-snapping sassy anthem "Bo$$," pop banga "Sledgehammer" and, of course, their summer smash "Worth It" which has only continued to dominate throughout the year — even in viral form.

Little Mix, on the other hand, are already on Studio Album No. 3, and their genre-hopping new effort saw the girls experimenting with tons of new styles, from the doo-wop-ish sound of "Love Me Like You" to the banging, fist-pumping "Hair" to their ultra catchy witchy singalong, "Black Magic."

It's safe to say that the two acts have served up some serious smashes to keep both the Harmonizers and Mixers pleased throughout the year. And now that the two both have albums out in 2015, we've been doing some thinkin' about the two: Which one ultimately stands out as the best girl group album of the year? We need your help to decide.

Place your vote below. We'll reveal the results right here on Monday, November 16 at 5 PM ET. Go, go, go!

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