The correct answer is A. DLP (Data Loss Prevention), because DLP solutions are specifically designed to detect, monitor, and prevent unauthorized transmission of sensitive data outside an organization. Information exfiltration occurs when confidential data is improperly transferred, leaked, or stolen, either intentionally or accidentally.

According to the Quentin Docter -- CompTIA A+ Complete Study Guide, DLP technologies enforce policies that restrict how data can be shared via email, cloud services, removable media, or network transfers. DLP systems can block, quarantine, or alert administrators when sensitive data patterns---such as credit card numbers or personal identifiers---are detected leaving the organization.

The Travis Everett & Andrew Hutz -- All-in-One Exam Guide explains that DLP focuses on data protection, not user authentication or device management. While IAM controls access to resources and MDM manages mobile devices, neither directly prevents data from being exfiltrated once access is granted.

The Mike Meyers / Mark Soper Lab Manual reinforces that SAML is an authentication framework and does not monitor data movement.

Because the question specifically addresses information exfiltration, the security control designed to prevent it is Data Loss Prevention, making A the correct answer.