Abudget in which more is spent than collected is in
a. overextension.
b. surplus.
c. balance.
d. deficit.

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."

well, i can't read it so i'll ask you questions about it : )

if you were a reader and you read the introduction, would you want to read more?

does it start with a question? if so, is it something you would want to read about?

and ask any friends or family for their opinion : )