The “bar”. Which we call a “Long John” here in the Midwest is every bit the doughnut that anything from Tim Horton’s. The original doughnuts, from my very limited research on the topic, were first developed in 17th century New York by Dutch immigrants who stuffed nuts and fruit into dough balls to keep the center from being soggy from frying. So, no hole. The ring shape was developed for the same reason as the fillings, to promote even cooking of the dough. So, Bismarcks, Crullers, Long Johns, pączki, Bear Claws, and cake and raised dough rings are all part of the lovely and wondrous doughnut family.
However, the ones with the hole look most like motorcycle tires so the post instantly becomes appropriate for this forum.