The correct answer is: D. paperclip
All attachment fields display as a paperclip icon in Datasheet View. This is because a paperclip is a common symbol for attachments. When you click on the paperclip icon, you will be able to view and manage the attachments for that record.
The other options are incorrect because they do not represent the correct symbol for attachments. Option A, icon, is too general. Option B, button, is not a common symbol for attachments. Option C, thumb tack, is a symbol that is sometimes used for attachments, but it is not as common as the paperclip.