Your ad can show to potential customers when your targeted language matches:

  • the customer’s browser setting
  • the customer’s Google interface language setting
  • the customer’s operating system language
  • the language of websites a user visits most often

The correct Answer is:

  • the customer’s Google interface language setting

Explanation: Language is targeted on the basis of potential customer’s Google interface language setting.

Read more here: https://school4seo.com/adwords-fundamental/your-ad-can-show-to-a-user-when-your-targeted-language-matches/