Already, Prime Minister Alexis Tsipras is struggling to contain a rebellion in his leftwing Syriza party that made his government dependent on votes from pro-European opposition parties to get the tough bailout terms approved in parliament.
Refer to the input text as context and select the correct relationship between 'Syriza' and 'Alexis Tsipras' from the available options.
Options: chief executive officer, distributed by, chairperson, product/material produced