What provides the best protection against data compromise in the event of physical theft of the device?

• A. Disk encryption
• B. Firewall
• C. Intrusion Prevention System
• D. Virtual Private Network

Answer: (A)

Disk encryption protects data at rest, so even if a device is stolen, the data remains unreadable without the decryption key. By encrypting the entire disk and requiring authentication or a trusted hardware key to unlock it, the attacker can’t access files, emails, or other sensitive information simply by powering on the device. The other options focus on defending data in transit or on the network: a firewall blocks unwanted network access, an Intrusion Prevention System detects or stops malicious traffic, and a VPN protects data while it’s moving over networks. Those don’t prevent exposure if the physical device itself is stolen. Disk encryption is the strongest safeguard for this scenario.