Is it ensure, insure, or assure?
c.1600, "action of choosing," from French option (Old French opcion), from Latin optionem (nominative optio) "choice, free choice, liberty to choose," from root of optare "to desire, choose," from PIE root *op- "to choose, prefer." Meaning "thing that may be chosen" is attested from 1885. Commercial transaction sense first recorded 1755 (the verb in this sense is from 1934). As a North American football play, it is recorded from 1954.