Answer
c) starting to allow trade when the world price is greater than the domestic price
Work Step by Step
When a country opens up to the trade of a good where its domestic price is lower than the world price, its producers can export that good and charge the world price. Therefore, producers benefit from the higher world price. However, the domestic price must then rise to the world price, hurting domestic consumers who must pay the higher price. Overall, the amount of trade increases because this country now exports.
