Utilize the input text as a context reference, choose the right relationship between 'Berkshire Hathaway' and 'Warren Buffett' from the options.
Options: chief executive officer, owner of, owned by, platform

Home / Nation & World / Berkshire buying Precision Castparts for $32B Berkshire Hathaway Chairman and CEO Warren Buffett speaks May 5, 2014, during an interview with Liz Claman on the Fox Business Network in Omaha, Nebraska.
chief executive officer