Q Which fingers were the two long digits on the forelimbs of Tyrannosaurus?

While early dinosaurs are believed to have had five fingers, the digits of theropod dinosaurs regressed and reduced in number over time.
In Tyrannosaurus, the bone for the middle finger still exists within the palm of the hand. However, because typical theropods are thought to have lost their ring and pinky fingers first, we know that the two functional fingers on its forelimbs are actually the “thumb and index finger.”