If the U.K. pound sterling appreciates relative to the New Zealand dollar, it means that the pound can buy more New Zealand dollars than before. This generally makes New Zealand goods more expensive for U.K. consumers, while New Zealand consumers will find U.K. goods relatively cheaper.
As a result, the U.K.'s demand for New Zealand goods will decline. Therefore, the correct response is:
The U.K.'s demand for New Zealand goods will decline.