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Beneath the preview of the upload box are different file types.
To allow any file type to be uploaded, leave all the boxes unchecked.
To allow only a specific or several specific file types, select those by checking the checkbox. The upload box will update to reflect the allowed file types.
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At the bottom of the question editor, mark the question as required (toggle on) or optional (toggle off) for the respondents.
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Analyzing the Response Data
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