How is 6:00 AM written in military time?

In military time, the clock operates on a 24-hour format rather than the traditional 12-hour clock. When converting a standard time, such as 6:00 AM, to military time, you simply express it in four digits. The hour component is represented with two digits, and since 6:00 AM falls within the first half of the day, it retains the same numeric value. Thus, 6:00 AM is represented as 0600 in military time—'06' for the hour and '00' for the minutes.

This formatting eliminates ambiguity and clearly indicates the time as early morning, making it essential for military operations and communications. The other responses do not represent 6:00 AM and instead correspond to different times in the morning, clearly indicating their incorrectness in this context.