Using radio button to accept Yes/No questions is best because the field accepts only one of the options. It is better than a dropdown because there are only two choices - either of them can be selected by a single click
Here is the code to create a yes/no radio button.
<input type=”radio” 
       name”affirmative”
       value=”yes”
       checked>
            Yes
</input>
<input type=”radio”
       name”negative”
       value=”no”>
            No
</input>
Demo
Also see: HTML Form input examples
