Critical Reasoning

In free-trade countries such as the United States, if there is a coal-supply disturbance which increases international coal prices, domestic coal prices will also be affected whether such free-trade countries import some or none of their coal.

A. When there is a disturbance in the international coal supply, free-trade countries' domestic coal producers cannot participate in international coal markets.
B. As long as a free-trade country has sufficient domestic supply to meet domestic demand, domestic coal prices are barely affected, if at all, by international coal-supply disturbances.
C. Even if a free-trade country usually sells most of its domestically produced coal within its borders, that country remains part of the international market for coal.
D. Even if international coal prices spike, free-trade countries that export little or no domestically produced coal can keep domestic coal prices constant.
E. When there is a disturbance in the international coal supply, non-free-trade countries' domestic coal producers are affected by international coal markets.

OA C

Am I missing something? I dont see the question here.

Thanks
Vineesh