For this purchase, Martin could be considered by the buying center to be the user.
A user is someone who use a product or a person who bought a product or goods for their personal use or for their own usage.
Martin is considered by the buying center a user because he is the only person that uses the printer.
Therefore the correct answer is user.
Learn more about who is a user here:https://brainly.com/question/14567128
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