How does darius justify hi assumption of power in the behistun inscription? what is his relationship to ahuramazda, the zoroastrian god, and what role does divinity play in human affairs?

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."