In order to display basic True/False questions, simply add the following CSS to your stylesheet. :empty
identifies answer buttons that have no content and hides the element using display: none
In your Google sheet table simply put the correct answer (whether "True" or "False") in the correct answer column and the incorrect (whether "False" or "True") in the first incorrect column. Leave the remaining two answers blank.
Likewise, you could have questions that offer only 3 multiple choice answers.