What are examples of prescription drugs that are opioids?

answer; the correct answer to the above statement is to increase the production of milk in a herd of milk cows, the highest producing cows were chosen as the mother;

it is a better alternative

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."