Answer;
-Phanerozoic Eon
Step-by-step explanation;
-Phanerozoic Eon is the geological time scale Eon is the longest period of time.
-Phanerozoic Eon is the span of geologic time extending about 541 million years from the end of the Proterozoic Eon (which began about 2.5 billion years ago) to the present. The Phanerozoic Eon is divided into three eras—the Paleozoic, the Mesozoic, and the Cenozoic. These eras span from about 540 million years ago to the present. We live now in the Cenozoic Era.