The phylogenetic species concept may not be useful for microbial species because

A) microbes are not neatly divided by species barriers.
B) it is only useful if organisms reliably pass down genes to offspring.
C) the genomes of microbes are mixed together by horizontal gene transfer, resulting in a mosaic-like genome.
D) all of the above

Microbial Species

A group of microorganisms, such as bacteria, archaea, fungi, and protists, that share similar genetic characteristics and are distinct from other groups.

Horizontal Gene Transfer

The swapping of genetic material in single or multiple-celled organisms through mechanisms that bypass the "vertical" passing down of DNA from ancestor to descendant.

Phylogenetic Species Concept

A concept in biology that defines a species based on the smallest group of individuals that share a common ancestor, representing one branch on the tree of life.