Building Phylogenetic Trees Can Be Challenging When Horizontal Transfer Has

Multiple Choice

Building phylogenetic trees can be challenging when horizontal transfer has occurred in bacteria. Why?

A) Trees cannot be accurately rooted when horizontal transfer has occurred
B) Virulent isolates evolve too rapidly to be captured in a phylogenetic tree
C) Lineages of bacteria from different locations are unrelated if horizontal transfer has occurred
D) Genetic differences between organisms are usually assumed to have occurred in a stepwise fashion