No such thing as trick questions. I am afraid for you if this is how you think and approach the PMP. PMI has hundred of SME's in their payroll whose job is to make sure you don't pass. In other words to pass, you have to go to the deep end and know the material hence the term "situational". There are no direct or simple or trick questions that you find online or that give you clear choices or answers. This one you will have to earn, no shortcuts. All the best.
There are no "trick questions' on the exam, but every question requires you to *carefully* read the question and figure out what the question is asking for. It was my experience (and the experience of others on this board in other topics) that the plausible detractors are answers for similar processes, but not what the question is really asking. Generally, at least one and sometimes two, answers can be tossed right away, and the remaining answers have to be carefully considered.
I think everyone is over analyzing this, the PMP exam is based on the logic/formulas in the PMBOK. So this is (25 * 24)/2 equals 300.
As someone who passed the exam, I would give the following advice. Read the question very carefully to ensure you understand it, but after you have done that don't then over analyze things.
You have a total of 25 stakeholders on your team. Due to some unavoidable circumstances, two of your stakeholders leave the team and you are not replacing them, so you hire two part time employees. How many lines of communication does your project have now?
(a) 351
(b) 253
(c) 25
(d) 300
Two stakeholders leave and two new albeit part-time arrive so the base number remains at 25. (25*24)/2 = 300
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