The flow chart below indicates the hierarchical levels of the Linnaean classification system.

Which of the following organisms most likely share the most structural characteristics?
A.
Two organisms that are classified within the same class, but different orders.
B.
Two organisms that are classified within the same genus, but different species.
C.
Two organisms that are classified within the same kingdom, but different phyla.
D.
Two organisms that are classified within the same phylum, but different classes.