Historian: There is no direct evidence that timber was traded between the ancient nations of Poran and Nayal, but the fact that a law setting tariffs on timber imports from Poran was enacted during the third Nayalese dynasty does suggest that during that period a timber trade was conducted.
Your task
Describe how the argument proceeds — the technique it uses to reach its conclusion.
Common trap
Answers that describe a method the argument doesn't actually use.
Winning move
Track the role each statement plays, then match that to the choice describing the same moves.