Except among the Westernized upper class, people eat from a common plate or
group of dishes.

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."

answer; genetics;

answer; becoming friends with her roommate and joining the debate team; sarah's making friends with her roommate and joining the debate team are examples of relational needs

the answer is c. : )