Answer:
The geography affected independent city-states development because A. Mountains isolated city-states and D. Plains were barriers.
Step-by-step explanation:
The mountains acted as natural frontiers that were not so easy to overcome for a regular commute. Thus, societies put emphasis on becoming self-dependent for most of their needs.
The long stretches of open plains also proved to be barriers as they took a lot of time to be crossed. These two geographical aspects affected the development of the city-states.