与通胀有关的一题，变化关系理不清

18.   There are fundamentally two possible changes in an economy that will each cause inflation unless other compensating changes also occur. These changes are either reductions in the supply of goods and services or increases in demand. In a prebanking economy the quantity of money available, and hence the level of demand, is equivalent to the quantity of gold available.

If the statements above are true, then it is also true that in a prebanking economy

(A) any inflation is the result of reductions in the supply of goods and services

(B) if other factors in the economy are unchanged, increasing the quantity of gold available will lead to inflation

(C) if there is a reduction in the quantity of gold available, then, other things being equal, inflation must result

(D) the quantity of goods and services purchasable by a given amount of gold is constant（B）

(E) whatever changes in demand occur, there will be compensating changes in the supply of goods and services

其实这题就是B和C中选，不过我对题干的意思还是不太明白，请教NN每句话确切意思是什么？

文意：There are fundamentally two possible changes in an economy that will each cause inflation unless other compensating changes also occur.有两个基本量的改变任一一个的变话都会引起通货膨胀，除非另一个量的补偿作用也发生。These changes are either reductions in the supply of goods and services or increases in demand这两个量一个是货物或服务供给量的减少，一个是需求的增多。 In a prebanking economy the quantity of money available, and hence the level of demand, is equivalent to the quantity of gold available在一个prebanking经济下货币量充足，需求量水平和金钱水平相适宜（即货币量能够满足需求量，不会交易货币流量不足）。If the statements above are true, then it is also true that in a prebanking economy如果以上申明是真实的，那么，在此经济下它也一定是真实的。

A，任何的通货膨胀都是货物或服务的供给量减少引起的（错，因为忽略了另一个因素，即需求的增多）

B，如果别的因素在此经济下不变，增加货币供给量会造成通货膨胀（对，货币量增加会造成需求量的增加，成为通货膨胀的诱因，但是同时如果另一个因素产生的补偿效应无法发生，因为已经说别的因素不变了。另一个因素为货物或服务供给的增加）

C，货币供给量减少会造成通货膨胀（错，货币供给减少，那么需求就会减少，只会造成通货紧缩）

D，货物和服务的支付价格固定不变（错，与推论无关的，同时价格不变供给需求量也不会变化，根本不可能通货膨胀了）

E，不管需求如何变化，总会有货物或服务的补偿效应抵消（错，不仅和推论无关，而且任何学经济的都知道绝不可能总存在这样巧的补偿效应）

非常感谢指点！其实，真的看内容，此题的逻辑难度很低，比起很多千回百转的support、assumption题要简单多了，可是逻辑题有时做错、不会做是因为无法理解题意。所以如果问GMAT的逻辑题分数能反映考生的逻辑思考能力，这个结论的assumption 是：考生做错题的原因不是理解错误，或考题的文字都能被考生正确理解。