What is the relationship between Syriza and Alexis Tsipras in the context of the input sentence. Choose an answer from: 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.

PT5M5S 620 349 Autoplay On Off Video feedback Video settings ﻿ PM Alexis Tsipras faces Syriza mutiny Eurozone clinches deal with Greece Marousi: Business has been so brisk in the giant Kotsovolos appliance and electronics store in this upper-middle-class suburb of Athens that you might think a sale was on.

Answer: chairperson