Utilize the input text as a context reference, choose the right relationship between Syriza and Alexis Tsipras 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 splintering of the more vehemently 'anti-memorandum' faction of Syriza and the renewed electoral mandate for Prime Minister Alexis Tsipras reduces the immediate political uncertainty that had arisen with the decision to call snap elections," said the Fitch ratings agency, referring to the memorandum of understanding signed for the bailout.

Answer: chairperson