i'm studying for the exam myself, but i'll try to answer your queries to the best of my knowledge
first, you need to choose the solution that will really solve the problem you-or the project- are facing
secondly, kindly find my replies on your queries hereinafter;

1. you have to ask why the deliverable isn't accepted?and then you will pick the answer that will solve the problem but if you want to make sure that the deliverable meets the acceptance criteria you may review the requirement docs or the WBS dictionary based upon the choices you have in the questions as both of them include the acceptance criteria,however the trace-ability matrix doesn't
2. when a change is needed, you need to analyze its impact first on all the competing constraints and then look for options to minimize the impact then take it to the board.
   if it gets approved you need to update the relevant plans then inform stakeholders
3. this depends on the situation but what should solve the problem for good is to review the communication plan and the stakeholder management plan
4. also this depends but better to review both
5. some changes doesn't need to be sent to the board, if the changes doesn't affect the cost or the schedule or doesn't have a major impact maybe the project manager can approve them himself. this should depends on the level of authority the PM has and the change type

I hope that may answer your questions

Carolina, I don't know where these questions originate, so I'll provide some general guidance. Whenever you take your practice exams, count the ones you got wrong, review the correct answer, and reverse engineer the knowledge. Practice exams may include the reasoning and some might show where the answer is derived from. At that point, call that question a weakness and study the associated topic so you can improve your understanding.

Hello everyone! I often get confused when answering questions similar to the ones listed below and would appreciate your inputs.
1) If deliverable is not accepted by the customer, what should the Project Manager review first: scope baseline, requirement documentation or requirement traceability matrix? Or maybe a different document? Should the same documentation be reviewed if a deliverable had passed unnoticed?
2) When a change is needed, is it correct to say that first its impact in the project should be analyzed, then stakeholders need to be informed and then a change request submitted?
3) When stakeholders complain that they have not received information, should the PM send them the information immediately or review communication plan first?
4) When joining a project that was going on, should the PM first review the project management plan or the charter?
5) If a project team makes a change without consulting the change board, should the PM go ahead and submit the change request?
Thanks in advance for your help!