Which of the following file names are invalid in MSDOS? A. MYFILE.DOS B. CHECK$.(1) C. Verified.### D. Qwerty.1?3

The correct answer is B. CHECK$.(1).

A file name in MSDOS can be up to 8 characters long, and can include any combination of letters, numbers, and underscores. However, it cannot start with a number, and it cannot contain any of the following characters:

• Space
• ?
• *
  :
  ”
  <

  |
  /

Option A, MYFILE.DOS, is a valid file name.

Option B, CHECK$.(1), is not a valid file name because it starts with a number.

Option C, Verified.###, is a valid file name.

Option D, Qwerty.1?3, is a valid file name.