The core concept tested here is the understanding of 'scope' in project management. The correct answer is B, as 'scope' refers to the range of a project's objectives and deliverables, encompassing all the work required to complete the project successfully. Option A is incorrect because the budget is a separate aspect of project management. Option C is incorrect as the timeline refers to the project schedule, not its scope. Option D is misleading because the geographical area is not a defining feature of a project's scope.