Answer:
B
Explanation:
Had the same question and it was the correct answer
The correct answer is D.
If you don't include something in the subject line of an email the recipient might delete your message or send it to the spam folder. The whole purpose of a subject line is to include a compelling reason for the recipient to open the email and read it. If there is nothing in the subject line then the recipient will have no reason to open the email and might just automatically delete it of forward it to spam.
