What is indicated by a GMT watch in watchmaking?

A GMT watch is specifically designed to display the time in another time zone, which is why the chosen answer is correct. The term GMT stands for Greenwich Mean Time, the time standard that many time zones are based on. A GMT watch often features a rotating bezel or an additional hour hand that is set to represent a different time zone alongside the local time. This functionality is especially useful for travelers, pilots, or anyone who needs to track time across different regions efficiently.

The other options do not capture the primary function of a GMT watch. For instance, a watch that displays only the local time would not meet the definition of a GMT watch, as its design does not accommodate an additional time zone. Similarly, while some watches may include moon phase indicators or date functions, those features do not relate to the GMT classification, which is fundamentally about tracking time across multiple zones.