Which of the Following Situations Is the Best Example of a Commons

Which of the following situations is the best example of a commons dilemma?

A) Eric sorts his recycling even though his neighbours don't sort their cans and bottles
B) Michelle prefers electric heat, whereas Mitch prefers gas heat
C) Hugo will not drive unless there is no public transit available
D) because it's only one piece of paper, Janet doesn't recycle it
E) Pat and Mike disagree about whether to turn off the water while brushing their teeth