The answer would be A, or [tex]y = 15x + 20 [/tex]
Since every month it charges you 15$, and you pay an initial fee of 20$, then the answer would be [tex]20 + 15x = y[/tex].
And if we rearrange it, it would give us: [tex]y = 15x+20[/tex].
Hope this helped! c: