Which pairing of occurrence and date is correct?

A) origin of invertebrates-630 million years ago
B) origin of eukaryotic cells-2.1 billion years ago
C) origin of prokaryotic cells-3.5 billion years ago
D) chordate evolution-545 million years ago
E) All of the answers are correctly paired.

Eukaryotic Cells

Cells that contain a nucleus and other organelles enclosed within membranes, differentiating them from prokaryotic cells.

Prokaryotic Cells

Simple, single-celled organisms without a nucleus or other membrane-bound organelles, such as bacteria.

Invertebrates

Animals that lack a vertebral column or backbone, including groups such as insects, mollusks, and arachnids.