Oil producers get a high price for their oil when market supply is low

Which of the following most logically completes the passage?

Oil producers get a high price for their oil when market supply is low. But the price drops sharply when oil supplies are abundant. Thus, in high-output years, some oil producers keep oil stockpiles for one or two years, hoping to sell at higher prices in the future. This year's market supply of oil was the lowest in five years. It is nonetheless quite possible that a portion of this year's oil production will be stored into stockpiles, since _____________ .

(A) each of the last two years produced record breaking oil output
(B) the viscosity of this year's oil is no lower than the viscosity of the oil produced in each of the previous five years
(C) oil prices have not been subject to sharp fluctuations in recent years
(D) for some oil producers, this year's production was no smaller than last year's
(E) the practice of holding back part of one year's crop had not yet become widespread the last time the oil output was as small as it was this year