I feel that the question plus its 4 answers are a little vague, and they could use a little more detail. I also agree that "Project Team" is the best answer. Let me explain:
This is taken from pg 290 in PMBOK 6: "Manage Quality is considered the work of everybody - the PM, the project team, the project sponsor, the maangement of the performing organization and even the customer"
So why isn't the answer suppose to be D) Everyone? While everyone should be putting their work into the Manage Quality process to make sure the processes/deliverables are of the highest quality. The question asks for "Who is responsible for managing quality.
From the same paragraph on pg 290:
"In traditional projects, quality management is often the responsibility of specific team members"
Using that logic, this is how they came up with the answer B ) Project Team
In my humble opinion, the question itself is an example of poor quality and lazy writing. It could use a few more sentences to elaborate, ex. what type of project it is (agile vs traditional), and whether it is referring to the Manage Quality process or overall quality management, last but not least it did not ask who is solely responsible. This would eliminate confusion and inconsistencies.
Hope this helps,
Joe
