What is the country located in the country in the southern part of the Philippines

Explanation:

The archipelago lies to the east of the South China Sea and west of the Philippine Sea and the western Pacific Ocean. Nearby countries are Malaysia in the southwest, Indonesia in the south, Vietnam in the west, and Taiwan, and mainland China to the north.

the branch of biology that deals with the normal functions of living organisms and their parts.

the way in which a living organism or bodily part functions.

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."