What is the relationship between 'Marissa Mayer' and 'Yahoo' in the context of the input sentence.
Options: currency, chief executive officer, employer, position held

Credit Cards Auto Marissa Mayer Remaining Yahoo CEO with Twins on the Way Is a Big Sign of Progress Written by: Eric Reed 09/01/15 - 3:25 PM EDT NEW YORK (MainStreet) -- Tuesday brought the news that Yahoo CEO Marissa Mayer is pregnant with identical twins.
employer