If you go deep enough, all 3 can tear up the backside of your colon, and they do look long enough for it.

Apart from that, without lube, probably the middle one, due to bad angles for the drag and clenching sphincter. With lube, the first one, due to the largest flaring open, as well as steps down in width. Especially in the way out, risking tearing the sphincter or nearby skin, if you clench too hard at the wrong times.

Start small, and get proper toys, everyone.