Final answer:
The statements that describe shared characteristics are that the more characteristics organisms share, the more closely related they are, and shared characteristics can exist among organisms that belong to different species.
Step-by-step explanation:
When analyzing shared characteristics in organisms, two accurate statements stand out. First, C. The more characteristics organisms share, the more closely related they are. This is indicative of a common evolutionary history where organisms inherit traits from common ancestors. As organisms evolve, they accumulate differences, but those with a recent common ancestor will have more characteristics in common.
Second, E. Shared characteristics can exist among organisms that belong to different species. This sharing of traits across species is observed in the presence of homologous structures or genetic sequences, suggesting a shared evolutionary past. An example is the presence of an opposable thumb in both humans and other primates, signifying a shared ancestor.