PART A: What is the author's purpose in this text?

A
to bring attention to a new understanding of how social problems behave and how they might be improved
B
to encourage conservative politicians not to cut funding on projects that don't appear to be working
C
to remind people of the influences that tipping points have on social problems so they can prevent them from
happening
D
to reassure people that most social problems don't need interference and will eventually resolve themselves