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.

Whether Syriza leader Alexis Tsipras or his New Democracy opponent Evangelos Meimarakis triumph in the election on Sunday that is too-close-to-call, Mr Dallara said volatility induced by Greece "is highly likely to rear its head again.

Answer: chairperson