A、x-(5y-1)=x-5y+1.故本选项错误;B、3a-2(b-c)=3a-2b+2c.故本选项正确;C、2x+2(y-z)=2x+2y-2z.故本选项错误;D、6m-3(n+1)=6m-3n-3.故本选项错误;故选B.