In the asch studies, people named the wrong line even though they knew it was wrong this is called
a conformity
b group polarization
c deindividuation
d group facilitation

i feel as if they would both catch on before to long because they would see them to frequent

what words? are you talking about to complet what sentence

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."