In the context of the input sentence, determine the relationship between 'Syriza' and 'Alexis Tsipras'.
Options: headquarters location, chairperson, position held, brand

ATHENS, Sept 1 Greece's Syriza party will scrap a value added tax on private education if voted back to power in a snap election in September, a party statement said on Tuesday evening, as its leader Alexis Tsipras campaigned on the island of Crete.
chairperson