[ghaff]

Eh. As someone who has been involved with survey work--both giving and receiving--standard practice in this situation would probably be A and it wouldn't shock me if it had been covered in class. D is not wrong and might be the right answer if, e.g., emailing out a survey to a broader mailing list of people who don't have a close affiliation with you--i.e. you don't want to pester a general population. However, A is pretty much what is done for employee satisfaction surveys and things of that type.

[peteradio]

Is it a test on the trivia of typical survey conduct or a question to probe understanding of statistics? If its a trivia question then ask it like "What is the most likely way a survey would followup in the event of ...".