Country Y uses its scarce foreign-exchange reserves to buy scrap iron for recycling into steel；Although the steel thus produced earns more foreign exchange than it costs, that policy is foolish；Country Y's own territory has vast deposits of iron ore, which can be mined with minimal expenditure of foreign exchange.

Which of the following, if true, provides the strongest support for Country Y's policy of buying scrap iron abroad?

【选项】Furnaces that process scrap iron can be built and operated in Country Y with substantially less foreign.exchange than can furnaces that process iron ore.