Digital SAT Reading and Writing Practice Question #753

Most contemporary models of ancient urbanization assume that the earliest cities in Mesopotamia developed organically around centralized administrative hubs, such as monumental temples or royal palaces, which were necessary to manage vast agricultural surpluses. However, the recent excavation of Tell Brak in northern Syria complicates this traditional model. Evidence from the site suggests a "hollow city" layout where discrete, self-sustaining satellite settlements gradually expanded and merged inward over several centuries. ________, Tell Brak’s development appears to have been driven by a bottom-up amalgamation of communities rather than organized by a singular, top-down administrative core during its formative period. Which choice completes the text with the most logical transition?