[逻辑小分队] OG 2017 verbal 分册 184 题！！

Gortland has long been narrowly self-sufficient in both grain and meat. However, as per capita income in Gortland has risen toward the world average, per capita consumption of meat has also risen toward the world average, and it takes several pounds of grain to produce one pound of meat. Therefore, since per capita income continues to rise, whereas domestic grain production will not increase, Gortland will soon have to import either grain or meat or both.

Which of the following is an assumption on which the argument depends?

(A) the total acreage devoted to grain production in Gortland will not decrease substantially

(B) the population of Gortland has remained relatively constant during the country's years of growing prosperity

(C) the per capita consumption of meat in Gortland is roughly the same across all income level

(D) In Gortland, neither meat nor grain is subject to government price controls

(E) People in Gortland who increase their consumption of meat will not radically decrease their consumption of grain

各位大神求助啊，我能理解E是正确答案，但是不能理解B为什么错，如果这个地方的人少了呢，那total consumption不就有可能减少了么？？好纠结啊，对逻辑恐慌日益加深