Why are so many big cities located along the banks of a river

The cities, especially the largest ones have almost always been located along the banks of a river, usually a larger one. ... In the past, a major reason was the fertile soil, as the larger population needed more food, and the fertile deposits by the rivers enable high scale production of food. ( cite: google )

a chair, a bed, and a toothbrush

explanation:

plato users

given bodies of water

pacific / arctic / indian / southern

[ a ] the caribbean sea

[ b ] the northern ocean

[ c ] the atlantic ocean

[ d ] the barents sea

with this being the given answers