Utilize the input text as a context reference, choose the right relationship between 'Telstra' and 'David Thodey' from the options.
Options: chief executive officer, distributed by, brand, operator

David Thodey engineered a stunning turnaround at Telstra , extending its dominant position in the mobile sector, negotiating lucrative agreements with the government (twice) over the National Broadband Network, selling off non-core assets and cutting expenses.
chief executive officer