What is the relationship between 'Balfour Beatty' and 'LONDON' in the context of the input sentence.
Options: headquarters location, product/material produced, currency, industry

LONDON (Reuters) - British infrastructure group Balfour Beatty (BALF.L) issued a fresh profit warning on Thursday, saying it had found further problems in its business which are likely to tip it into another loss for 2015.
headquarters location