Utilize the input text as a context reference, choose the right relationship between 'Russell Group' and 'London' from the options.
Options: headquarters location, owner of, legal form, owned by

* Rolls-Royce's biggest shareholder ValueAct is in for the long haul Elsewhere, the London Stock Exchange Group began to reap the benefits of acquiring the Russell Group , as robust growth in the index business helped Europe’s oldest independent bourse post a 27pc rise in half-year adjusted operating profit to £366.1m.
headquarters location