Question

unit exam - evolution of populations
which of these is considered by scientists to be one of the most intense bursts of evolution in the history of the earth?
the cambrian explosion
the lunar extinction
the big upwelling

Explanation:

The Cambrian Explosion was a rapid diversification of life - forms on Earth. It led to the appearance of many major animal phyla in a relatively short geological time. There is no such thing as "the Lunar Extinction" in the context of major evolutionary events, and "the Big Upwelling" is not a well - known major evolutionary burst event.

Answer:

A. the Cambrian Explosion