If the only interactivity you get from your Word documents is someone clicking on one to read it, you'll find a world of opportunity in a somewhat hidden feature. Microsoft Word 2013's Developer tab is hidden by default, but once you enable it, you can add options such as in-document check boxes, radio buttons and drop-down lists to your work. You retain control over what appears in the lists and even how they look.
Add the Developer Tab (Optional)
Launch Word and either open an existing document or click "Blank document" on the splash screen.
Click the "File" tab, then click "Options" to open the Word Options window.
Click the "Customize Ribbon" link.
Click the "Main Tabs" menu from the Customize the Ribbon column if it is not already enabled.
Click a check mark into the "Developer" check box in the list. By default, this tab is unchecked. If it is already checked, leave it as it is. Click the "OK" button to close the Word Options window. You are returned to the Word document with the new Developer tab. You do not have to close or restart Word for the tab to appear.
Add a Drop-Down Menu
Click the "Developer" tab and make sure your cursor is on the page where you want the drop-down box. You can hover your cursor over any button until you see its pop-up tool tip name. Click the "Drop-Down List Content Control" button in the Controls section of the ribbon. The drop-down is added to the Word page.
Click the "Properties" button in the Controls section of the ribbon, opening the "Content Control Properties" window.
Enter information into the window's fields to customize your drop-down box as desired, such as choosing the drop-down box's title and color. Set optional controls for editing or deleting within the drop-down list, as desired.
Click into the Drop-Down List Properties section and click the "Add" button. Here is where you type all of the items users can select from in the list. Enter the "Display Name" for each individually, and the Value field is autopopulated. Click "OK" to add each to the drop-down list.
Click "OK" to close the Control Control Properties window and return to the Word document with the drop-down list box populated.
The Developer tab remains visible in Word, even after you shut down the software, until you return to the Options window and uncheck that box in the list.
These instructions are written for Microsoft Word 2013 users. Earlier or later versions of the software may behave differently.