Utilize the input text as a context reference, choose the right relationship between 'BG Group' and 'Royal Dutch Shell' from the options.
Options: platform, position held, parent organization, chairperson

Oil producers decline Oil producers, including Royal Dutch Shell (Xetra: R6C1.DE - news ) and BG Group (LSE: BG.L - news ) , headed south as Brent crude hovered just under $49 per barrel, the lowest level since January.
parent organization