Based on the results of this study, what questions remain unanswered? How can these questions guide future research?

you didn't even explain what study this is for. please give more context next time in order to receive help. thank you :)

the answer to your question is slate

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