Utilize the input text as a context reference, choose the right relationship between Syriza and Athens 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.

The Athens stock market also fell around 3 percent as the country's prime minister looked set to call early elections in a bid to quell a rebellion in his leftist Syriza party and seal support for a tough bailout programme.

Answer: headquarters_location