The conquistadors were driven primarily by the desire for gold.
a religious duty to acquire land for Spain.
an urge to distribute land to the native peoples.
a desire to have American Indians experience power and fame.

answer; if congress didn't act on certain requests;

the united states has a federal government. the president is the head of the federal government of the united states. however, each state forms its government for administration purposes. the powers of the state governments are exercised within restricted state boundaries. and citizens participate in this government by voting.

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."