Which of the following best describes a way to safely transmit Controlled Unclassified Information (CUI)? -Debra ensures all recipients have the required clearance and an official need-to-know before sending CUI via encrypted e-mail. -Paul verifies that the information is CUI, includes a CUI marking in the subject header, and digitally signs an e-mail containing CUI. -John submits CUI to his organization's security office to transmit it on his behalf. -Prudence faxes CUI using an Unclassified cover sheet via a Secret fax machine.