Since the 1960's South Korea Has Imported Iron and Copper

Since the 1960's South Korea has imported iron and copper because

A) it has never had the natural reserves of these nonrenewable minerals
B) industrial applications that require these metals has surged since then
C) it exported large amounts of these nonrenewable minerals in the 1950's and since then has not had enough to meet its own demands
D) rapid economic growth alone has outstripped the country's ability to meet demands
E) it is both cheaper and less polluting to import the minerals rather than mine for them in their own country