Contacting Support - AdSense Help: "What are AdChoices?
The AdChoices icon appears on sites that use Google's AdSense program to show ads. While Google often shows you ads based on the content of the page you are viewing, we also show some ads based on the types of websites you visit, view, or where you interact with an ad or other Google product supported by Google's advertising services. In doing this, Google doesn't know your name or any other personal information about you. Google simply recognizes the number stored in your browser on the DoubleClick cookie, and shows ads related to the interest and inferred demographic categories associated with that cookie."
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