Can dependencies in a critical path method be determined accurately?

Question

I am looking for an answer to a question I received during a test on PM theory:

In a critical path method, dependencies between activities can be:

1. accurately determined;

2. estimated approximately.

Answer 1

There are three types of dependencies: ones you can see clearly and are known with no uncertainty; ones you think you have but need to clarify; ones you cannot see because you do not know what you do not know. I would think the answer is 2. If the correct answer is one, then the author of the question has issues with illusion of being all knowing. Risk applies here as with every other area of projects.

Answer 2

Critical Path Method (CPM) requires dependencies to be accurately determined

Looks like your recollection of the question is inaccurate.

Critical Path Method (CPM) works like this:

1. You list all the activities required to complete a project.
2. You establish the precedence relationships (dependencies) among them. For each activity, list all the other activities that should have been completed prior before starting it.
3. With the above information you draw a network diagram.
4. The longest path in the network diagram is the Critical Path. If any of the activities in the Critical Path is delayed by a day, the entire project is delayed by a day. The activities not on the Critical Path may have some float (wiggle room).

Thus, unless you identify the dependencies accurately, you cannot apply the Critical Path Method.

So, most likely the question was:

"For applying the critical path method, dependencies between activities need to be 1. accurately determined 2. estimated approximately."