Explanation/Reference:
Explanation:
Multilevel security properties can be expressed in many ways, one being noninterference. This concept is implemented to ensure any actions that take place at a higher security level do not affect, or interfere with, actions that take place at a lower level. This type of model does not concern itself with the flow of data, but rather with what a subject knows about the state of the system. So if an entity at a higher security level performs an action, it cannot change the state for the entity at the lower level.
If a lower-level entity was aware of a certain activity that took place by an entity at a higher level and the state of the system changed for this lower-level entity, the entity might be able to deduce too much information about the activities of the higher state, which in turn is a way of leaking information. Users at a lower security level should not be aware of the commands executed by users at a higher level and should not be affected by those commands in any way.
Incorrect Answers:
A: The Bell-LaPadula model is a state machine model used for enforcing access control in government and military applications. This is not what is described in the question.
B: The information flow model forms the basis of other models such as Bell-LaPadula or Biba. This is not what is described in the question.
D: The Clark-Wilson model prevents unauthorized users from making modifications, prevents authorized users from making improper modifications, and maintains internal and external consistency through auditing. This is not what is described in the question.
References:
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 380