What it certifications are available in this field of a programmer

the president has the power to appoint federal judges, ambassadors, and other "principal officers” of the united states, subject to senate confirmation of such appointments.

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; (true);

answer; preconventional;