Answer:
T. Rex would have 4 chambered heart because it is closely associated with Parrot due to common ancestry.
Step-by-step explanation:
T. Rex is Tyrannosaurus rex which was basically considered to be cold-blooded and related to reptile but to some recent findings of fossil related to T. Rex shows that they are warm-blooded and they are related to bird family which includes chicken, parrot, and ostriches.
The T. Rex had four chambers in its heart. The proof is that the parrot had four chambers in its heart and the T Rex and the parrot have a typical family. So, the parrot and the T Rex well offer qualities that are similar.
Also, the parrot and T Rex are firmly related as opposed to the T Rex and the caiman.