--- Bob, where are you working now?

--- I used to work in a small company, but I ________ a job in some bigger companies.

A．have sought

B．had sought

C．was seeking

D．am seeking

如果物体的运动状态发生了变化，说明该物体的[ ]

A．速度的大小可能改变 　 　

B．速度的方向可能改变

C．加速度一定改变 　

D．物体所受得合外力一定不为零