Answer:
Option (2)
Step-by-step explanation:
The Cenozoic era started from about 65 million years back to the present. It started after the great Cretaceous-Tertiary mass extinction event. During this time, the continents took the present shape and floras have continuously evolved, producing a variety of species. A good number of animals occurred during this period such as the horse, mammals, and also one of the greatest significance of this era is the first appearance of humans and its evolution.
Thus, the correct answer is option (2).