Final answer:
The most appropriate hedging strategy for the U.S. firm in this situation would be to buy dollars forward.
Step-by-step explanation:
The most appropriate hedging strategy for the U.S. firm in this situation would be to buy dollars forward. By buying dollars forward, the firm can lock in a specific exchange rate for the future when paying for the Korean imports. This way, even if the Korean won depreciates, the U.S. firm will not be affected as they have already secured the desired exchange rate.