Utilize the input text as a context reference, choose the right relationship between Man Group and LONDON from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

LONDON (ShareCast) - (ShareCast News) - Shares (Berlin: DI6.BE - news ) in Man Group (LSE: EMG.L - news ) slumped following a press report that the chairman of the hedge fund manager's China unit, Li Yifei, has been taken into custody by Chinese authorities to assist with a police probe into market volatility.

Answer: headquarters_location