In the context of the input sentence, determine the relationship between 'Repsol' and 'Petroleum'.
Options: brand, chief executive officer, creator, product/material produced

BP, Statoil (Xetra: 675213 - news ) , Anadarko Petroleum Corp. , Repsol and Total (Swiss: FP.SW - news ) are the main foreign energy firms in Algeria.
product/material produced