Answer:
B. Anarchy.
Step-by-step explanation:
Logically, semantically and meaningfully, the only word that can fill in the blank is anarchy. This is the case because the phrase is making reference to installing a few rules and procedures to abide by in the classroom, lest it devolves into: anarchy. Anarchy, by its etymology, means the absence of governing principles or rules, that is to say, the lack of rules.