Making use of the sociological perspective encourages:

Making use of sociological perspective encourages one’s self in challenging of their beliefs which they held and influenced them as they grow. It is because sociological perspective is a perspective of which is responsible in having a person have views of behavior and how it is being done in connection with the society. It tries to gain and learn perspective views of how a person behave in a society and how they were able to do or adjust with beliefs they learn or things they do with the society or  as a whole. It is also a way of having views about the structure of the society and how these would affect them as a whole.

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."