The three largest oil companies BP, Royal Dutch Shell (LSE: RDSB.L - news ) and BG Group (LSE: BG.L - news ) alone make up 13.3pc of the index by weight.
Refer to the input text as context and select the correct relationship between 'BG Group' and 'Royal Dutch Shell' from the available options.
Options: parent organization, member of, owner of, founded by