Interface CheckboxItem

A question item that allows the respondent to select one or more checkboxes, as well as an optional "other" field. Items can be accessed or created from a Form. When used in a quiz, these items are autograded.

// Open a form by ID and add a new checkbox item.
var form = FormApp.openById('1234567890abcdefghijklmnopqrstuvwxyz');
var item = form.addCheckboxItem();
item.setTitle('What condiments would you like on your hot dog?')
    .setChoices([
          item.createChoice('Ketchup'),
          item.createChoice('Mustard'),
          item.createChoice('Relish')
    ])
    .showOtherOption(true);