How would this play out for future civilizations that develope from these ancient civilization? Complete sentence please

Where does the availability of water pose the greatest problem

Impressions of tropical swamp plants were observed on rocks in polar regions. the impressions were dark black imprints, which means the fossils are examples of ( 1 ) the fossils tell us that polar regions ( 2 ) ( 1 ) a. carbonization b. mineralization c. trace fossils ( 2 ) a. had tropical plants that can grow in ice b. might have had a diffierent climate in the past c. will have abundent vegitation

Rainbow trout is non- native to the united states. however this species is breeding with the native gula yltrout acientistrecently observed that the hola trout were becoming exitinct what is the cause of their extinction