When setting up questions for your online survey, it's important to choose the most appropriate answer component. Please read our article on the different types of answer components available in Citizen Space to get familiar with what they all do.
If you only want the respondent to be able to select one of the options from a multiple choice list then you will need to use radio buttons:
Use a check box when you want to give your recipients the opportunity to select more than one option:
These two options in the 'Add an answer component' dropdown reflect what the respondent will be able to do, e.g. they will be able to select one or select all that apply.