Why do some questions have square buttons while others have circles?
Closed-ended question types will either have circular radio buttons or square checkbox buttons, depending on the question settings. The shape of the button determines how many answer choices a respondent is allowed to select.
Radio buttons indicate that respondents can only select one answer from the list of choices. When a respondent selects an answer choice, all other answer choices are deselected automatically.
Checkboxes indicate that respondents are allowed to select multiple answers from the list of choices.
On questions that allow multiple answers, you can set a range or a limit on how many choices respondents must select. Learn more: Making Survey Questions Required