This topic examines the basic knowledge of computers.

The operation flow of word document encryption method using file menu is as follows: 1. Use Word to open the document to be encrypted. 2. Select the Save As menu item in the File menu to open the Save As dialog box. 3. In the Save As dialog box, click the Tools button and select the General Options menu item to open the Save tab. 4. Enter the password in the open password and modify password text boxes in the * * * options area of the file. 5. Click the OK button. 6. Save the file and complete the encryption of the file at the same time.

So the correct answer is C.