Which is the valid filename assign in MS-DOS? A. Ram*.txt B. Ram?.doc C. Ram_$.txt D. None of above

The correct answer is: A. Ram*.txt

A valid filename in MS-DOS must meet the following criteria:

• It must be at least 1 character and no more than 8 characters long.
• It can contain any combination of letters, numbers, and underscores.
• It cannot start with a number.
• It cannot contain any of the following characters: / \ : * ? ” < > |

Option A, Ram.txt, meets all of these criteria. The asterisk () is a wildcard character that can represent any number of characters. So, Ram*.txt could represent any file name that starts with “Ram” and has any number of characters after that.

Option B, Ram?.doc, does not meet the criteria because it starts with a question mark (?).

Option C, Ram_$.txt, does not meet the criteria because it contains the dollar sign ($).

Option D, None of above, is also incorrect because Option A is a valid filename.