Take context from the input text and decide on the accurate relationship between 'Syriza' and 'ATHENS' from the options provided.
Options: stock exchange, headquarters location, operator, owner of

ATHENS Aug 21 Greece's new Popular Unity party of far-left rebels from the leftist Syriza party will seek a mandate to form a government as the third-biggest group in parliament, a senior party lawmaker told Reuters on Friday.
headquarters location