What is the relationship between Metro Bank and London in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Metro Bank now has more than 35 branches open, most of which are concentrated in London and the South East, and has continued to report strong customer and deposit growth despite ongoing losses.

Answer: headquarters_location