Which of the following statements is always TRUE about sister taxa on a phylogenetic tree?

A)Sister taxa are always the result of speciation events that result in two new genera.
B)Sister taxa always share a most recent common ancestor that is not shared with any other taxon on the phylogeny.
C)Sister taxa are always the result of the most recent divergence event represented on a phylogeny.
D)Sister taxa are always defined by shared ancestral characteristics that have been modified in all other taxa in the phylogeny.