I think the correct answer should be ‘C’.
The option provided by Parvathy and marked by the user as correct does not even appear as one of the possible answers.
What do you think?
You are correct @Antonio_Perez! *.doc* will filter .doc as well as .docx.
Why others are not the right fit here?
Option A: Will only work for .doc extensions
Option B: Not a valid expression to filter files with .doc & .docx.
Option D: Not a valid expression.