Add “Java beans” as a negative keyword
Exclude “Programming” as a topic
Add “Coffee beans” as a topic
Refine the ad text of the ad so that it is clear that the advertiser is only selling Java coffee
Only exclude the irrelevant sites that do not directly mention Java coffee that are appearing in the Placement Performance Report
The correct answer is:
Just as you can target pages in the Google Display Network about certain subjects – like cars or music – you can also exclude by topic to keep your ads off webpages whose themes aren’t relevant to your customers.
A type of keyword that prevents your ad from being triggered by a certain word or phrase. It tells Google not to show your ad to anyone who is searching for that phrase.
For example, when you add “free” as a negative keyword to your campaign or ad group, you tell AdWords not to show your ad for any search containing the term “free.” On the Display Network, your ad is less likely to appear on a site when your negative keywords match the site’s content.
Read more here: https://support.google.com/adwords/answer/105671?hl=en