The statement that best explains the differences between the democracy of the Athenian polis and the structure of the Roman Republic is:
The senate of the Roman Republic was composed of wealthy patrician magistrates whereas the Athenian ecclesia and Council of 500 were made up of various citizens drawn by lot from different territories within Athens.
This statement highlights the differences in social class representation and the methods of selecting governing bodies in the two political systems, illustrating the distinct approaches to democracy in Athens and the structure of governance in the Roman Republic.