Some plans benefit from document enhanced security. In this case, you have the option to improve the encryption of your document with a dedicated password, known as the ‘Answer’. Documents using this option have a Question and Answer you have to fill when uploading them. See Question/Answer FAQ related to this topic to know more about it.
If a document doesn’t use the Question/Answer (enhanced security feature), the document is still encrypted on our servers. The only difference is that with the Question/Answer just you and your recipient can open the file.