Utilize the input text as a context reference, choose the right relationship between Telstra and David Thodey 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.

Former Telstra chief executive David Thodey has been appointed chairman of CSIRO, Australia's troubled flagship scientific body.

Answer: chief_executive_officer