The question is asking us to identify the pair that is not correctly matched. Let`s analyze each option to determine if it is correctly matched or not:

1) Kuroshio: Warm ocean current. This pairing is correct. The Kuroshio is a warm ocean current that flows northward along the eastern coast of Japan.

2) Labrador: Warm ocean current. This pairing is incorrect. The Labrador Current is a cold ocean current that flows southward along the eastern coast of Canada.

3) Benguela: Cold ocean current. This pairing is correct. The Benguela Current is a cold ocean current that flows northward along the western coast of southern Africa.

4) Oyashio: Cold ocean current. This pairing is correct. The Oyashio is a cold ocean current that flows southward along the eastern coast of Japan.

From the analysis above, we can see that option 2 is not correctly matched. The Labrador Current is a cold ocean current, not a warm ocean current.

Therefore, the correct answer is option 2.