How does the author illustrate the idea that young people can be hands-on in the environmentalist movement in their own communities in "We Live on Planet A: Young People Rally for Their Rights"? A. by describing the details of the exciting opportunities Erica Wallstrom provides to her students

B. by describing the 2018 gathering of young people at the UN Climate Change Conference

C. by mentioning that they can join clubs that promote recycling

D. by mentioning that Stanford University has worked to create a better environmental curriculum