It is important to remember that .

A.
groups are more effective than individuals
B.
ad hoc groups often skip the norming stage
C.
groups need not progress through each stage in order, and some even backslide, particularly if membership changes
D.
standing groups will progress through each stage only once
E.
every group will go through each of the five stages

The correct answer is letter "C": groups need not progress through each stage in order, and some even backslide, particularly if membership changes.

Explanation:

While assigning duties to groups it is suitable to measure their progress but not to every single step. Eventually, if they achieve their goal or not will be identified but while the work is in progress there should be milestones at specific points to find out if the group is in the right path or if actions must be needed.

Another factor to consider is if members of the group change constantly which represents a drawback for the completion on time of the objectives the entity could have set.

answer; /// the above statement is (true);