Utilize the input text as a context reference, choose the right relationship between 'Worldpay' and 'London' from the options.
Options: headquarters location, founded by, original broadcaster, parent organization

British payments processor Worldpay joined the London Stock Exchange on Tuesday in an initial public offering valuing the company at 4.8 billion pounds ($7.4 billion), the biggest flotation in what had been a lacklustre year for listings in Britain.
headquarters location