What is the relationship between Sheryl Sandberg and Chief Operating Officer in the context of the input sentence. Choose an answer from: 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.
Text: SAN FRANCISCO, July 6 (Reuters) - Facebook Inc's Chief Operating Officer Sheryl Sandberg is taking a seat on the board of SurveyMonkey, the online polling company that was run by her late husband, Dave Goldberg.
user
position_held
assistant