Which of the following should be used to ensure an attacker is unable to read the contents of a mobile device's drive if the device is lost?

Full Disk Encryption (FDE) is the correct choice because it encrypts the entire storage drive of a device, making all data unreadable without the correct decryption key. If a mobile device with FDE is lost or stolen, an attacker cannot access the data even if they remove the drive and attempt to read it on another system. Trusted Platform Module (TPM) is a hardware component that provides secure cryptographic operations and storage for keys, but it doesn't encrypt the entire disk on its own. Error-Correcting Code (ECC) is used to detect and correct data corruption, not for security against theft. Hardware Security Module (HSM) is a physical computing device that safeguards and manages digital keys, but like TPM, it doesn't directly encrypt the entire disk.