Complete installation of computer within 3 months is an example of

rules
programme
project
schedule

The correct answer is D. schedule.

A schedule is a plan for the completion of a task or set of tasks, with specific deadlines for each task. A schedule is often used to manage the time and resources required to complete a project.

A rule is a principle or regulation that must be obeyed. Rules are often used to govern behavior or to ensure the safety of people or property.

A program is a set of instructions that tells a computer what to do. Programs are often used to automate tasks or to create new software.

A project is a set of tasks that are undertaken to achieve a specific goal. Projects are often complex and require the coordination of multiple people and resources.