Explanation
A parametric estimate is an estimate that uses a mathematical model to calculate the expected duration, cost, or quantity of a project activity or component based on historical data and known variables1. A parametric estimate is often used when there is a high degree of similarity between the current project and past projects, and when the project can be measured in standard units, such as hours, meters, or workstations2. In this scenario, the 25 workstations per hour represents a parametric estimate because it uses historical data and a standard unit to calculate the expected quantity of workstations that the project team can install per hour.
The other options are not correct because:
Option B is incorrect. Planning is a process that involves defining the scope, objectives, tasks, deliverables, schedule, resources, and risks of a project or a project component3. Planning is not an estimate, but rather a result of estimation and analysis.
Option C is incorrect. Report project is not a valid term in project management or business analysis. A report is a document that communicates the status, progress, results, or findings of a project or a project component to the relevant stakeholders4. A report is not an estimate, but rather a product of estimation and measurement.
Option D is incorrect. Timeboxing is a technique that involves allocating a fixed amount of time for a specific activity or deliverable, and then adjusting the scope or quality to fit within the time limit.
Timeboxing is not an estimate, but rather a method of estimation and prioritization.
References:
Parametric Estimating, section "Description of Change"
Parametric Estimating: Definition, Formula, Example, Advantages & Disadvantages - Project Management, section "What is Parametric Estimating?" Planning, section "Description of Change" Report, section "Description of Change"
[Timeboxing], section "Description of Change"