In a network diagram, what signifies an activity's earliest finish time?

The earliest finish time of an activity in a network diagram is calculated by taking the early start time of that activity and adding the duration required to complete the activity. This relationship is crucial for understanding how activities are sequenced and how they fit within the overall project timeline.

When you add the early start time to the activity's duration, you determine the point in time when that activity must finish at the earliest, assuming that no delays occur. This information is pivotal for project scheduling and helps project managers identify potential bottlenecks or to ensure that project milestones are met.

In contrast, the other options do not accurately describe the calculation of an activity's earliest finish time. The total time for the project encompasses all activities and is not specific to a single activity's timeline. The minimum time required to complete an activity may refer to its shortest duration but does not incorporate the necessary starting point in time. Lastly, the deadline set by stakeholders may influence project planning but does not directly pertain to the technical calculation of an activity's earliest finish time within a network diagram. Thus, the definition provided in the correct answer aligns perfectly with project management principles and scheduling techniques.