Scientists break down evolution into which two categories?

microevolution and macroevolution

macroevolution and genetic drift

microevolution and mass extinction

natural selection and macroevolution

Option A, microevolution and macroevolution

Explanation:

Scientist have categorized evolution base on the time scale  into following two categories

a)Macroevolution – These are the processes which take a long time to occur such as formation of a new species, extinction of any rare species etc, Also it affects a large mass of population or the entire population

b)Microevolution – In this,  the processes of change take a short time and usually they impact only a certain set of species for a shorter time period.  

Thus, option A is correct.