The rhetorical situation that best reflects the appeal known as pathos is:
"A community leader speaks at an Earth Day event, telling a story about a group of high school students who cleaned up their neighborhood streets in their spare time."
Pathos is an emotional appeal that aims to persuade the audience by appealing to their emotions, such as pity, sympathy, joy, or anger. In this scenario, the community leader is telling a story that evokes positive emotions, such as pride and admiration, towards the group of high school students who made an effort to clean up their neighborhood. The story is likely to touch the audience's hearts, inspiring them to take action towards environmental conservation, which is the main message of the Earth Day event.