Utilize the input text as a context reference, choose the right relationship between 'Halliburton' and 'HOUSTON' from the options.
Options: headquarters location, creator, director/manager, legal form

HOUSTON (Reuters) - Business is so tough for oilfield giants Schlumberger NV and Halliburton Co that they have come up with a new sales pitch for crude producers halting work in the worst downturn in years.
headquarters location