When a new system is to be implemented within a short time frame, it is MOST important
to:

A.
finish writing user manuals.

B.
perform user acceptance testing.

C.
add last-minute enhancements to functionalities.

D.
ensure that the code has been documented and reviewed.

Explanation:
It would be most important to complete the user acceptance testing to ensure that the system to
be implemented is working correctly. The completion of the user manuals is similar to the
performance of code reviews. If time is tight, the last thing one would want to do is add another
enhancement, as it would be necessary to freeze the code and complete the testing, then make
any other changes as future enhancements. It would be appropriate to have the code documented
and reviewed, but unless the acceptance testing is completed, there is no guarantee that the
system will work correctly and meet user requirements.