To solve the problem $63+(56+37)-(28-12)$, Linda writes the steps below. In which step the first mistake was written?  Step $1$: $=63+56+37-28+12$  Step $2$: $=63+37+56-28+12$  Step $3$: $=100+56-28+12$  Step $4$: $=156+28+12$  Step $5$: $=156+40$  Step $6$: $=196$ 
选项为:A:Step $1$  B:Step $2$  C:Step $3$  D:Step $4$  E:Step $5$  请回答其中一个选项.