Right answer from comprehension

Question

From the passage I have to answer the following question:

According to the passage, which of the following was an important source of revenue in medieval France?

1. Cheese
2. Wool
3. Olive oil
4. Veal
5. Wine

The given answer is 5 (wine), but there is no clue for that answer. I guessed olive oil because it has relation with land. Is it right?

Agricultural progress provided the stimulus necessary to set off economic expansion in medieval France. As long as those who worked the land were barely able to ensure their own subsistence and that of their landlords, all other activities had to be minimal, but when food surpluses increased, it became possible to release more people for governmental, commercial, religious and cultural pursuits.

However, not all the funds from the agricultural surplus were actually available for commercial investment. Much of the surplus, in the form of food increases, probably went to raise the subsistence level; an additional amount, in the form of currency gained from the sale of food, went into the royal treasury to be used in waging war. Although Louis VII of France levied a less crushing tax burden on his subjects than did England’s Henry II, Louis VII did spend great sums on an unsuccessful crusade, and his vassals-both lay and ecclesiastic-took over spending where their sovereign stopped. Surplus funds were claimed both by the Church and by feudal landholders, whereupon cathedrals and castles mushroomed throughout France.

The simultaneous progress of cathedral building and, for instance, vineyard expansion in Bordeaux illustrates the very real competition for available capital between the Church and commercial interests; the former produced inestimable moral and artistic riches, but the latter had a stronger immediate impact upon gross national product. Moreover, though all wars by definition are defensive, the frequent crossings of armies that lived off the land and impartially burned all the huts and barns on their path consumed considerable resources.

Since demands on the agricultural surplus would have varied from year to year, we cannot precisely calculate their impact on the commercial growth of medieval France. But we must bear that impact in mind when estimating the assets that were likely to have been available for investment. No doubt castle and cathedral building was not totally barren of profit (for the builders, that is), and it produced intangible dividends of material and moral satisfaction for the community. Even wars handed back a fragment of what they took, at least to a few. Still, we cannot place on the same plane a primarily destructive activity and a constructive one, nor expect the same results from a new bell tower as from a new water mill. Above all, medieval France had little room for investment over and above the preservation of life. Granted that war cost much less than it does today, that the Church rendered all sorts of educational and recreational services that were unobtainable elsewhere, and that government was far less demanding than is the modern state-nevertheless, for medieval men and women, supporting commercial development required considerable economic sacrifice.

Answer 1

The key word relating to wine is vineyard. There is no mention made of olives.

Still, the question is quite difficult, since the passage mentions wine in exactly one sentence, and in an indirect way. Vineyard expansion is never mentioned as important, per se, but rather as a example of where excess resources were spent productively.

Answer 2

This line " the latter had a stronger immediate impact upon gross national product." shows that vineyard was an important source of revenue in medieval France.

There's no mention of any oil in the passage. In comprehension passages, answers are to be written from paragraph itself. No guess is allowed as the answer.

Before attempting the answers,it is advisable to read the passage thrice and jot down the important points so as to understand the meaning of the passage.