If grain prices double then the average price of a loaf of bread will rise ... ...

If grain prices double then the average price of a loaf of bread will rise between 10 and 15 percent, whereas the price of grain-fed beef will come close to doubling.

Which one of the following would, if true, most contribute to an explanation of the phenomenon described above?


(A) Farmers engaged in very large-scale cattle production generally try to reduce the labor costs involved in the production and sale of beef.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in PT70 (Oct 2013): Logical Reasoning B