Utilize the input text as a context reference, choose the right relationship between 'Eurogroup' and 'Jeroen Dijsselbloem' from the options.
Options: chairperson, founded by, location of formation, distribution format

Eurogroup president Jeroen Dijsselbloem - who represents all 19 finance ministers - questioned whether Mr Tsipras could implement measures which he had attacked as "blackmail" and “humiliation” only seven days ago.
chairperson