Final answer:
In the Triassic, synapsids did not completely disappear. Therapsids and archosaurs survived.
Step-by-step explanation:
In the Triassic period, synapsids did not completely disappear. Therapsids and archosaurs survived. Therapsids were a group of reptiles that included the mammal-like reptiles, while archosaurs were a group of reptiles that included dinosaurs and crocodiles.
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