Through which country does the Prime Meridian run?

The Prime Meridian is defined as the meridian (0 degrees longitude) that passes through the Royal Observatory in Greenwich, England. This line serves as the starting point for measuring longitude, dividing the Eastern and Western Hemispheres. Because the Prime Meridian is a critical reference point for navigation and mapping, its location in England is significant historically and geographically. The designation of Greenwich Mean Time (GMT) has also made this location pivotal in timekeeping around the world. Thus, England is the correct answer as it is the country through which the Prime Meridian runs.