To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) McDonalds screensaver - This option is the correct answer. The McDonalds screensaver virus is a documented hoax virus. It was a popular hoax that claimed that opening an email attachment called "McDonalds Screensaver" would infect your computer with a virus. However, this virus does not actually exist.
Option B) Alien.worm - This option is incorrect. The Alien.worm virus is not a documented hoax virus. It is possible that there may be viruses or malware with similar names, but this specific virus is not a documented hoax.
Option C) Merry Xmas - This option is incorrect. The Merry Xmas virus is not a documented hoax virus. It is another name for the W32/Bagle@MM worm, which is a real virus that spreads through email attachments.
Option D) Adolph - This option is incorrect. The Adolph virus is not a documented hoax virus. It is possible that there may be viruses or malware with similar names, but this specific virus is not a documented hoax.
The correct answer is A) McDonalds screensaver. This option is correct because the McDonalds screensaver virus is a documented hoax virus.