In prokaryotes new mutations accumulate quickly in populations, while in eukaryotes new mutations accumulate much more slowly.
The primary reasons for this are:.
A) Prokaryotes have short generation times and large population sizes.
B) Prokaryotes have random mutations while eukaryotes can target genes for mutations; thus mutations may not accumulate as quickly in eukaryotes but they are more useful to the organism.
C) The DNA in prokaryotes is not as stable as eukaryotic DNA and is thus more likely to mutate.
D) Prokaryote mutations are less effective than eukaryote mutations in providing variation for evolution.

Option A

Explanation:

In Prokaryotes the the rate of new mutations is much more as compared to the eukaryotes. The rate of accumulation of mutation is slow in case of  eukaryote because their generation is long as compared to prokaryotes.

Prokaryotes have short generation time and large population size which enables them to accumulate the mutation quickly.

The machinery is also not that complex when it comes to prokaryotes. Transduction, conjugation and tranposable elements. So, the changes during these processes leads to mutation in the prokaryotes and can be observed quickly due to their small generation.

the missing space is phylum

idk what happened..you tell