Final answer:
b. Temporary
A project is defined by PMBOK as a temporary endeavor with a start and end, designed to create a unique product or result. Task deadlines and budgets are central to project success, exemplified by product launch timings in competitive markets.
Step-by-step explanation:
The Project Management Body of Knowledge (PMBOK) Guide defines a project as a temporary endeavor undertaken to create a unique product, service, or result. That means it has a defined beginning and end in time, and therefore defined scope and resources. Notably, a project can indeed be multifunctional as it often incorporates different tasks that involve various teams and individuals with different skills. However, the distinguishing factor highlighted by PMBOK is the temporary nature of projects, rather than their multifunctionality or the consumption of human resources.
Considering the example of designing a new video game controller, it illustrates the importance of project deadlines. Task deadlines are significant because missing one can jeopardize a product's launch, especially in markets where timing is critical, such as the holiday season, or in competitive scenarios where being first can capture the largest market share. Projects are often limited by a budget, which can dictate the scope and resources available and can also influence the success of the project.