The monkeys took many photos, most of which were out of focus or poorly composed. Could not sorting through the essentially random photos that the monkeys took, and selecting those with most artistic potential, and perhaps cropping them to improve the composition, be considered a creative act?
Sorting through them might be making a compilation, which has separate protection under copyright law. It wouldn't extend to the photos in the compilation, but only the compilation itself…
I have no idea if sorting through monkey photos would count, that's a question best addressed to an IP lawyer.
Cropping photos I could possibly believe to be a creative act, but I would find it absurd to consider selecting only the in-focus photos to be a "creative" act. I would put that decision on par with alphabetizing the phone book.
The person who took the photos, since that would be the creative act. Sorting through the photos and selecting the good ones is also a creative act, but it is a derivative work because the original images are copyright protected. The difference comes about because monkeys are not capable of owning copyright, and hence are not capable of "creative acts" as far as copyright is concerned.