The major key signatures you listed correspond to the following keys:
- D major: 2 sharps (F#, C#)
- B major: 5 sharps (F#, C#, G#, D#, A#)
- G major: 1 sharp (F#)
- A major: 3 sharps (F#, C#, G#)
If you're looking for just "the major key signature," it could refer to any of these keys depending on your context. Could you please clarify if you are asking for a specific one to be named?