Answer:
Option (3)
Step-by-step explanation:
Cambrian age ranged from 540 to 480 million years back. It is the first period within the Paleozoic era. During this time a huge number of organisms occurred marking the great Cambrian explosion. Trilobites first appeared in this period.
Jurassic represents the second period of Mesozoic era that ranged from 200 to 145 million years back. This was time when the dinosaurs were the dominant species on earth. The climatic condition during this period was very intense an warm.
A great evolution has taken place from the time of Cambrian to the Jurassic and to the recent age. The organisms that occurred in the early stage were quite simple in comparison to the present day complex organisms.
Both these two distinct periods are rich in a number and variety of fossil assemblage but these fossils are different from each other because life on Earth has been constantly changing through geological time.
Hence, the correct answer is option (3).