Final answer:
Brazil exhibits a comparative advantage in the production of iron ore.
Step-by-step explanation:
When a country can produce a good at a lower opportunity cost than another country, we say that this country has a comparative advantage in that good. Comparative advantage is not the same as absolute advantage, which is when a country can produce more of a good. In the case of Brazil and Australia's advantage in the production of iron ore, Brazil exhibits a comparative advantage because it can mine and export iron ore more efficiently and at a lower opportunity cost compared to most other countries.