What is the relationship between 'Russell Investments' and 'London Stock Exchange Group' in the context of the input sentence.
Options: parent organization, manufacturer, chief executive officer, owned by

July 9 (Reuters) - China's CITIC Group Corporation is in negotiations to acquire Russell Investments from London Stock Exchange Group Plc in what is expected to be a roughly $1.8 billion deal, according to people familiar with the matter.
parent organization