Which of the following statements BEST reflects the idea of declining marginal benefit?
A) The more I ate of the candy, the better it tasted.
B) As we purchased more and more lumber, the price kept going up until we could no longer afford to buy the lumber we needed.
C) Our family really needed our first car, and we got a second car because it was convenient, but we see no reason to buy a third car.
D) The chairs were selling for $20 for the first chair, but the price was reduced by one dollar for each additional chair purchased.