LONDON, Sept 8 (Reuters) - A look at valuations illustrates how regulatory concerns and stubbornly low energy prices have stoked investor anxiety over Royal Dutch Shell (Xetra: R6C1.DE - news ) 's planned takeover of British rival BG Group (LSE: BG.L - news ) .
Refer to the input text as context and select the correct relationship between 'BG Group' and 'Royal Dutch Shell' from the available options.
Options: developer, parent organization, stock exchange, chairperson