Answer:
D). Impersonal communication.
Step-by-step explanation:
The example provided here demonstrates 'impersonal communication' which is a type of communication that is specifically associated with social roles informally and superficially. 'Impersonal' as the name suggests, it implies a communication without including or considering 'personal emotions or relationships'.
These types of communications usually include communication between a sales representative and customer(potential). These types of communications mostly include interaction with e-mails or social networking instead of directly or personally communicating with each other. Thus, as Melinda uses a less direct method to communicate her message(posting casual Friday policy on bulletin board), so, she adopts the 'impersonal communication' method which is option D.