Utilize the input text as a context reference, choose the right relationship between Merkel and Germany from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

An EU source reported that Merkel and Schaeuble, whose complex decade-long partnership in government is a source of fascination for Germany watchers, had "major differences" over the terms of the Greek rescue last week.

Answer: headquarters_location