What is the relationship between 'Halliburton' and 'HOUSTON' in the context of the input sentence.
Options: chairperson, industry, headquarters location, employer

HOUSTON (Reuters) - The strong valuation of engineering and construction firm KBR Inc. ( KBR.N ) will likely prompt directors of parent company Halliburton Co. ( HAL.N ) to vote to give KBR shareholders a chance to exchange stock in Halliburton for their newly listed business, analysts said.
headquarters location