During the 1950s and 1960s people believed that modernization was a cure for the various social and economic problems found in many less-developed nations.

it would be d). more resources must be obtained to attain that combination of goods and services

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; (trauma);