Nigeria is one of the world's largest oil exporters yet many nigerians remain poor because of

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."

dude the first thing it says is that copied answers will get a zero. plus it would take anyone on an incredibly long time to answer. ive seen 2 people asking the exact same question and their questions got taken down. i have the assignment too, and im in the progress of doing it. i suggest going to a more private website, because this is the first place teachers look.