Complete the text with who, why, where and which.

People who want to protect the environment are usually careful about the origin of their food. Food _____ comes from local producers is OK, but the countries _____ farmers grow exotic fruits are often thousands of kilometres from our shops. A good example is kiwi fruit ____ comes by plane from New Zealand. The boxes of fruit arrive at our airports _____ lorries are waiting to transport them to supermarkets. The supermarkets ____ sell this product are often out of town, si people ____ buy kiwi fruit must drive there. All in all, that's a lot of boxees and fuel - a lot of waste. That's _____ imported food is bad for the environment.