Take context from the input text and decide on the accurate relationship between 'Syriza' and 'Athens' from the options provided.
Options: operator, developer, headquarters location, chief executive officer

The Athens General Index (.ATG) has fluctuated sharply this year, which has seen left-wing Prime Minister Alexis Tsipras's newly elected Syriza government wrangle with European Union and International Monetary Fund lenders in bitter bailout talks.
headquarters location