Hmmmmm.... All of 'em! LOL My bass here have a pretty narrow diet. It's almost all bluegills, with some baby bass (mostly eaten by juv's), some crayfish, and some dragonflies thrown in here and there.
So... if my bass are mistaking my lures for BG's, then... all of 'em?
I try to help them out some by using "BG colors", esp in clearer water. But bluegills don't always, even often, look like what most manufacturers call "BG" color. Probably bc most fisherman recognize bluegills in spawning coloration. But most of the year, BGs are not so vividly dressed, esp in clear water, and esp for younger BGs, which most bass eat. I talk about this a bit on one of my summer videos -the "Late Summer" one, with swim jigs in that case.
Crankbaits, esp: What invariably gets my heart going while perusing the racks at a tackle shop, or the catalogs, are potential BG colors. And I have "bluegillized" a lot of cranks. I use and show one in my "Early Fall" video.
A lot of this is in my head, I know. But hey!, it's my head that going fishing, isn't it? That said, I'm sure that accuracy in image/motion (what RichZ has called "Identity Profile" or IDP) could be important, if they could be accurate enough. And just painting some chunk of plastic or wood in spawning bluegill colors doesn't go too far.
What I have only just begun to do is play around with some of the high end swimbaits that do appear to offer a much more accurate look. It remains to be seen how well these hold up in the IDP department after the bass gain experience with them.
I've come to recognize that the what I call "economic negotiations" between predator and prey are most important. I've also found that some lures are simply more difficult for fish to learn are "not food" than others. Two that come to mind are the stick-worms, and a nifty little creation that's been around for some time but no one seems to know, is the Lil' Fishie now sold by Creme. Great little lure. Someone ought to run with that design; It needs some tweaking in the larger sizes.