Which of the following technologies is the best choice to convey urgent and highly sensitive information? telephone fax letter e-mail dispatch radio

Using e-mail to send messages is the best choice to convey urgent and highly sensitive information. E-mail is just a conversation between you and the recipient. So it is the best when it comes to when you are sending a highly sensitive information. While telephone fax letter and dispatch radio may need to use a mediator to transfer messages which violates the confidentiality of the information.