I was frustrated because I couldn’t figure out how to get a bunch of pictures in google drive to show up to create an album in google photos. most of the solutions involved downloading the images, unzipping, and uploading them into photos. and, if you are trying to free up space in your google drive, that is the way to do it. in this case, however, I just needed the suckers to show up on my pick list. sometimes the answers are right in front of us. it seems from the comments on the post that the option shown in settings might be recent, but it was there for me.