Which technique requires an expert to provide a reliable time estimate for completing an activity?

The one-point estimate technique involves an expert providing a single, definitive time estimate for completing a specific activity. This approach relies heavily on the expert's experience and judgment, making it vital for project planning when precise timelines are necessary. The one-point estimate provides a clear expectation, though it may not account for variability or uncertainty associated with the task.

Although it can be quick and straightforward, this technique doesn't incorporate any range of estimates, which means it may not capture the potential for variations in time. In contrast, the three-point estimate technique takes a more comprehensive view by considering optimistic, pessimistic, and most likely durations, allowing for a more nuanced understanding of project timelines. Other options like cost estimation focus primarily on financial aspects rather than time, and duration forecasting typically refers to predicting the length of a project rather than obtaining a single expert-driven time estimate. Thus, the emphasis on a reliable, singular time estimate from an expert clearly identifies the one-point estimate as the correct technique in this context.