The correct answer is D. www.yahoo.fr.
A domain name is a unique identifier for a website on the Internet. It is used to locate and access websites on the World Wide Web. Domain names are made up of two parts: the top-level domain (TLD) and the second-level domain (SLD). The TLD is the part of the domain name that comes after the last dot. The SLD is the part of the domain name that comes before the last dot.
In the case of www.yahoo.fr, the TLD is “fr” and the SLD is “yahoo”. The TLD “fr” is the country code top-level domain for France. The SLD “yahoo” is the name of the website.
A valid domain name must meet the following requirements:
- It must be at least 2 characters long.
- It must be at most 63 characters long.
- It must start with a letter or a number.
- It must contain only letters, numbers, and hyphens.
- It must not start or end with a hyphen.
- It must not contain two consecutive hyphens.
- It must not be the same as a reserved word.
- It must be available for registration.
In the case of www.yahoo.fr, the domain name is not valid because it does not meet the requirement that the TLD must be a country code top-level domain. The TLD “fr” is the country code top-level domain for France, but the website is not located in France.