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.