<em>Answer: In economics, the law of increasing costs is a principle that states that to produce an increasing amount of a good a supplier must give up greater and greater amounts of another good. ... If the economy is at the maximum for all inputs, then the cost of each unit will be more expensive.</em>
I think it is B. 1950's, but that is just a guess so if I'm wrong then I'm sorry
Hope this helps. :)
Answer:
This would mean it is looking back to events or evidence that has already occurred rather than looking ahead for evidence to support a theory.