Which statement regarding the distribution of wealth by the mid-19th century is most accurate?

the answers is b.   environments.

the answer to your question is:

strong-mayor system

2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."