Which of the following refers to data that email content filtering provides?

The choice that refers to data provided by email content filtering is about the probability that messages are legitimate or spam. Email content filtering is a security technique used to analyze incoming and outgoing email messages. It utilizes various criteria, including content analysis, sender reputation, and known patterns of spam behavior, to determine the likelihood of a message being spam or legitimate.

By assessing these factors, content filtering solutions can assign a probability score indicating whether a message is spam, allowing organizations to prevent malicious or unwanted emails from reaching users' inboxes. This filtering process is crucial in protecting networks from phishing attacks, malware, and other email-borne threats, enhancing overall cybersecurity posture.

The other choices focus on different aspects related to email management or analytics but are not directly linked to what email content filtering specifically provides regarding spam detection and legitimacy assessment.