After drag & drop the ‘Attachment Question’ type, you can give the option to attach any file from the Survey Page.
Under “Advanced Option” available within Attachment Question Type, user can restrict file upload size and file extensions for particular file upload. Upload size can range between 1 MB – 5 MB.
Supported types for file extensions are csv, doc, docx, html, htm, jpg, jpeg, ods, odt, pdf, png, ppt, pps, rtf, sxw, tab, txt, text, tsv, xls, xlsx.
These restrictions applied to the question give validations to survey responder at time of survey submission.