To create a Person question type:
Select Person from the Question Type menu
Enter your question text
Select Person Or Organisation & Person
Person will show the user one menu all of users on your account
Organisation & Person will show the user two menus - Organisations and Users
Select your preferred Attributes
If you would like to, enable Enter Name Manually. This will create a box where the user can type in a name, rather than selecting from a menu.
Click on Preview to review your question
Click on Save to save and create your question