Which of the following statements is NOT true A. The Biba model states that a process running at security level k can read only objects at its level or higher. B. Mandatory access controls refer to the security policies that are enforced by the system. C. The policy that allows individual users to determine who may read and write their files and other objects is called discretionary access control. D. The Bell-LaPadula model is widely used for enforcing the integrity policy.