Gatekeepers – the people who control access of information into the buying center and the sharing of information among the members in the buying center. Sometimes a gatekeeper may directly influence the final decision by not providing some critical information to the buying center. For example, someone
form the purchasing department or the assistant/secretary of a CEO may act as
a gatekeeper by not allowing the seller to contact the decider, the influencer or the user in the buying center, hence preventing the flow of information to them. D is the right answer.