I believe the answer is: A. An elementary student with special needs
Advocate meant speaking in favour of other people in order to support them in a certain way. We need to advocate the people who are either do good in society or facing huge adversities in their life. Elementary students with special needs are considered to be a group of citizens that would face a huge adversities in their life and need to be supported.
well one could be a environmentalist and one could be a kid
Belief that America will grow bigger and bigger
First one is static
Second one is round
Third one is flat
Last one is dynamic