This graphic shows an outline. A list titled overcrowded city streets. There are two numbered lists below. 1, Cars are becoming too numerous on city streets. 2, The air is becoming polluted. 3, The noise level is rising. 1, More money from the city government should go to public transportation. 2, A subway system should be built. 3, People should be encouraged to carpool to work and school.

This outline is an example of

cause and effect.
order of events.
problem and solution.
order of importance.

problem and solution

Explanation:

C. Problem and solution

Explanation:

I did the test and got it right

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."