Which of the following is an element of PERT?

The correct choice highlights "Time" as a fundamental element of PERT, which stands for Program Evaluation and Review Technique. PERT is a project management tool designed to analyze and represent the tasks involved in completing a given project, with a particular focus on the time required to complete each task and the dependencies between those tasks.

In PERT, time is crucial because the method helps project managers estimate the minimum time needed to complete a project. It does so by assessing the individual tasks, their durations, and their relationships, ultimately allowing for better scheduling and resource allocation. This focus on time also assists in identifying critical paths within the project, which are the sequences of tasks that determine the overall duration of the project.

The other options, while relevant to project management, do not encapsulate the essence of PERT. Gantt charts are more aligned with task scheduling rather than the analysis of time and dependencies, while cost analysis and quality assurance pertain to financial and operational aspects, respectively, rather than the explicit timeline management that PERT emphasizes. Thus, the focus on time as a key element within PERT sets it apart as the correct choice.