The employee was ousted from the office

The correct answer is D. expelled.

To oust someone means to force them to leave a place or position. The other options are not as accurate because they do not convey the sense of being forced to leave.

• Pushed: This could mean that the employee was physically pushed out of the office, but it could also mean that they were simply encouraged to leave.
• Thrust: This word has a more forceful connotation than pushed, but it does not necessarily mean that the employee was forced to leave.
• Forced: This is the most accurate option because it clearly conveys the sense that the employee was made to leave against their will.
• Expelled: This is also an accurate option, but it is more specific than forced because it implies that the employee was removed from a place or position.