There are no sharps or flats in C Major.
The C major scale...
There are no flats or sharps. Its relative major scale is C major, which has all of the same notes.
E Major
D major isn't actually a note. D major is a major scale based on the note D (D natural) and the scale has two sharps (F sharp and C sharp). There isn't anything special about D major since it requires both an F sharp and a C sharp, the most 'special' scale is C major since there are no flats or sharps needed.
The major scale with 2 sharps is D major, they are F and C sharp.
There are no sharps or flats in C Major.
C major has no sharps or flats.
A major
The three sharps in A major are F, C, and G.
The major scale with five sharps is B major. The five sharps, in written order, according to the key signature, are F#, C#, G#, D#, A#.
The B major scale has 5 sharps: F#, C#, G#, D#, A#.
The D major scale has F# and C#.
C major and A minor both have no sharps or flats.
The C major scale...
C major scale and A minor.
C