Which dramatic genre purports to be serious but, in fact, deals with human issues on only the most superficial level, embellished with spectacular staging, flamboyant dialogue, and highly suspenseful and contrived plotting?

Melodrama

Explanation:

Melodrama is a theatrical genre that began to develop in the 18th century, influencing the dramatic arts to the present day. Its specificity is the use of music and dramatic action (spoken dialogues), but different from opera, for using incidental music to express the emotional charge of the characters and the situations in which they are immersed.

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."

you answered your own : -/