Which of the Following Hypothetical Viruses Would Likely Show a "Cactus-Shaped

Multiple Choice

Which of the following hypothetical viruses would likely show a "cactus-shaped" population phylogeny?

A) a mutualistic virus that is vertically transmitted
B) a highly virulent virus, like Ebola, that kills its host before the buildup of any immunity
C) a highly virulent virus that results in lifelong immunity and therefore can only infect individuals that have never encountered any of the virus' strains
D) a virus that can reinfect previously infected hosts via escape mutants