In this task, you will be presented with a question and you have to answer the question based on your knowledge. Your answers should be as short as possible.
Example: Who were the builders of the mosque in Herat with fire temples ?
Example solution: Ghurids
Example explanation: This is a good example. Ghurids were the builders of the mosque in Herat with fire temples.

Problem: What is the postcode district for the area straddling the border between the Royal Borough of Greenwich and the London Borough of Bexley in South London ?
Solution: DA18