Which of the following fields would determine how an email document is sent?

The field that determines how an email document is sent is the Disposition. In the context of email and data handling, the Disposition field defines the behavior or method by which the email is processed and delivered. This can include various actions such as whether the email should be sent, returned, or marked for further processing. It essentially instructs the email system on how to handle the message.

While the Content Type, From, and To fields are indeed important for email construction, they do not directly dictate the sending process itself. The Content Type specifies the format of the message (such as plain text or HTML), the From field identifies who is sending the email, and the To field indicates the intended recipient(s). However, it is the Disposition that encapsulates the rules for sending, handling, or interacting with the actual email transmission, making it the correct answer for determining the sending method of an email document.