What is the relationship between 'Turkmenistan' and 'ASHGABAT' in the context of the input sentence.
Options: employer, subsidiary, headquarters location, developer

ASHGABAT (Reuters) - The four countries planning a gas pipeline from Turkmenistan to Pakistan and India via Afghanistan will in September pick a company to lead construction, paving the way to the start of work on the project, the Turkmen president said on Saturday.
headquarters location