D, because whether or not the rivers flow into the mediterranean has no effect on early civilization.
survival of the fittest, in other words the Darwinian evolutionary theory. hope this helps!
An exclave is a portion of a state or territory geographically separated from the main part by surrounding alien territory (of one or more states). Many exclaves are also enclaves. Enclave is sometimes used improperly to denote a territory that is only partly surrounded by another state.
