The correct answer is: D. simulation
A simulation is the use of a model in an attempt to identify and/or reflect the behaviour of a real person, process, or system. Simulations can be used to test new ideas, to train people, or to predict the outcome of future events.
A master is a person who has control over a group of people or things. A decision is a choice between two or more options. A plan is a detailed proposal for doing or achieving something. None of these options are correct answers to the question.