How Does the Phenomenon of Horizontal Gene Transfer Muddle the Concept

Question

How does the phenomenon of horizontal gene transfer muddle the concept of monophyletic groups?
A)Monophyletic groups are based on the concept that a particular group of species descended from a common ancestor.When horizontal gene transfer occurs in the common ancestor,any species to which it gives rise can no longer be considered descendent species.
B)Monophyletic groups are based on the concept that a particular group of species descended from a common ancestor.When horizontal gene transfer occurs,not all of the genes in a species were inherited from the common ancestor.
C)Monophyletic groups are based on the concept that members of a particular group of species are related to one another at a particular taxonomic rank.However,a species that undergoes horizontal gene transfer no longer belongs to that taxon and the group is no longer monophyletiC.
D)Monophyletic groups are based on the concept that members of a particular group of species are related to one another at a particular taxonomic rank.An unrelated species that undergoes horizontal gene transfer can become more closely related to members of a different group,and the group is no longer monophyletic.

Accepted Answer

Horizontal gene transfer introduces genes from sources other than the common ancestor, complicating the genetic lineage and making it difficult to define monophyletic groups based solely on descent from a common ancestor.