Which targeting option should an advertiser use when trying to reach 25-30 year old males?
Interest category targeting
you can reach a specific set of potential customers who are likely to be within a particular age range, gender, parental status, or household income using this demographic targeting option. Keep in mind that demographic targeting is an option to narrow your targeting. In other words, it helps prevent people outside of the your chosen demographics from seeing your ads.
Read more here: https://support.google.com/adwords/answer/2580383