The competition watchdog said in March that it had granted permission for British Gas Trading (BGT) - a subsidiary of Centrica (LSE: CNA.L - news ) , the UK's biggest energy supplier - and Northern Powergrid to appeal against Ofgem's price control decision.
Analyze the relationship between 'British Gas' and 'Centrica' within the context of the input sentence.
Options: member of, publisher, owned by, business division