Sally really likes jon and accepts a date with him whenever he asks. she likes sim much less and accepts a date with him only occasionally. sally then falls in love with someone else and informs both jon and sim that she will no longer go out with them. jon quickly stops asking her out, but sim persists for several months. sim's persistence is most likely an example 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."