Which line shows the first error in the solution?

6x + 4 = 3x - 8 ( 1 )

6x - 3x + 4x = 3x - 3x - 8 ( 2 )

3x + 4 = -8 ( 3 )

3x + 4 - 4 = -8 - 4 ( 4 )

3x = -4 ( 5 )

3x/3 = -4/3 ( 6 )

x = -4/3 ( 7 )

Aline 3

Bline 4

Cline 5

Dline 6