Some argue that because attaining governmental power in democracies requires building majority coalitions, it is a necessary evil that policymakers do not adhere rigorously to principle when dealing with important issues, but rather shift policies as they try to please different constituents at different times.
Your task
Find the assumption the argument requires in order for its conclusion to hold.
Common trap
Answers that would help the argument but aren't strictly required (sufficient, not necessary).
Winning move
Negate each choice — the right one breaks the argument when negated.