Which of the following statements is incorrect in relation to electronic mail (email)? a. electronic mail has been around for over three decades; faster and cheaper than paper mail it is a popular application; unfortunately, like paper mail, some 9 out of 10 messages are junk mail (or spam) b. the user agents (mail servers) run in the background and are intended to be always available c. messages sent by the user agent must be placed in a standard format; a basic ASCII email contains header fields such as: To, From, and Sender; a MIME email contains MIME content types such as: text, image, audio, and video d. none of the above