Utilize the input text as a context reference, choose the right relationship between Glencore and Ivan Glasenberg 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.

China not impossible to read While Glencore chief executive Ivan Glasenberg last week declared the Chinese market was "impossible to read", Mr Mackenzie disagreed.

Answer: chief_executive_officer