Question

The development of____ factored into the development of complex organisms.

Ozone
Oxygen
Cyanobacteria
All of the above

The end of the Paleozoic Era was signaled by____.

The development of humans
Mass extinction of land and sea animals
The development of organisms with hard parts
Both a and b

Reptiles evolved from an ancestor of amphibians that developed a(n)____.

Egg with a strong outer shell that kept it from drying out
Hard set of teeth
Thick eyelid
Long tail

Answer 1

D.

B.

A.

Step-by-step explanation:

Answer 2

The development of Ozone, Oxygen, Cyanobacteria factored into the development of complex organisms. The correct option is the last option.

The end of the Paleozoic Era was signaled by mass extinction of land and sea animals. The correct option is the second option.

Reptiles evolved from an ancestor of amphibians that developed an egg with a strong outer shell that kept it from drying out. The correct option is the first option.