A.
Homeotic genes were first identified in invertebrates, but their homologs were found in almost all organisms.
B.
All homeotic genes contain consensus sequences that result in a specific DNA-binding motif.
C.
In vertebrates, homeotic genes are organized into two distinct clusters.
D.
All homeotic genes encode transcription factors that direct further gene expression.
E.
Homeotic genes exhibit a relationship between their order on the chromosome and the timing of their expression.