Please help me this due today

1 the swimmer is using her arms to move through the water and her legs to do the same.

2. The kid is using his legs to peddle the peddles.

3. the girl is using her arms to push her wheel chair because she can't use her legs.

4. the ballerina is jumping in the air being very flexible because she is streching  her arms and legs  

Explanation:

it is loom ps i took the test

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."