Question

Which event came first? The age of reptiles Amphibians leave the water Trilobites are one of the dominant species on Earth Early humans arise on Earth​

Answer 1

F1 development of the ozone layer

S2 sharks and trilobites abundant in oceans

T3 plants and animals colonize land

F4 dominance of reptiles >> dominance of mammals

Answer 2

Trilobites are one of the dominant species on Earth

We know it's not D, the age of reptiles was just a "wee" bit before humans, and amphibians came after trilobites.