You _____come to his office. Our boss won't be back until next week.   [ ]

A. haven't to                    

B. won't have got to    

C. haven't got to                

D. don't have got to

因式分解

（1）4a³b²-12a²b

（2）-a³+15ab²-9ac²

（3）m²（m-1）-4（1-m）²

（4）（x²+4）²-16x²．