Given the task definition and input, reply with output. In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.

A central business district (CBD) is the commercial and business centre of a city. In larger cities, it is often synonymous with the city's 'financial district'. Geographically, it often coincides with the 'city centre' or 'downtown', but the two concepts are separate: many cities have a central business district located away from its commercial or cultural city centre or downtown.
why is the cbd found in the centre of the city