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You will see options for Rich Text Content Control
or Plain Text Content Control 
which allows you to add an accessible text box for writing in. Example: If you are making a form that someone is filling out online, you can select either the Rich Text or Plain Text Content Control, and a text field will show up that allows the individual to click and write in the box that looks like this:
Another option that is given is the Check Box Content Control
which allows you to add a checkbox to your document.
Example: If there is a “circle yes or no” question on a document, use the Check Box Content Control instead to make it accessible:
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Under the Developer tab, there is also an option to use the Date Picker Content Control which allows you to insert a date picker to your document.
Example: Perhaps you are asking someone to fill out their birthday online. Instead of having them type out the date manually, the Date Picker Content Control allows them to select the date by using a calendar provided:
There are other Content Controls provided in the Developer tab and by hovering over them, it will give a brief description of what they are and what they are used for.
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