Answer: Option C
Explanation: Missionary selling is a form of physical sales in which the marketer gives information to a customer who will impact the decision to purchase. It is an implicit sales technique; the aim is not just to make a sale but actually to get data into the possession of a main decision-maker.
These individuals are highly knowledgeable and are experts in their fields and generally holds high positions in their organisations. Thus from the above we can conclude that the correct option is C.