Explanation: The security challenges for DRM are as follows: Key hiding: It prevents tampering attacks that target the secret keys. In the key hiding process, secret keys are used for authentication, encryption, and node-locking. Device fingerprinting: It prevents fraud and provides secure authentication. Device fingerprinting includes the summary of hardware and software characteristics in order to uniquely identify a device. OTA provisioning: It provides end-to-end encryption or other secure ways for delivery of copyrighted software to mobile devices. Answer: B is incorrect. Access control is not a security challenge for DRM.