Which of the following statements pertaining to the Bell-LaPadula model is TRUE if you are NOT making use of
the strong star property?

A.
It allows “read up.”

B.
It addresses covert channels.

C.
It addresses management of access controls.

D.
It allows “write up.”

Explanation:
Three main rules are used and enforced in the Bell-LaPadula model:
The simple security rule, the *-property (star property) rule, and the strong star property rule. The simple
security rule states that a subject at a given security level cannot read data that reside at a higher security level.
The *-property rule (star property rule) states that a subject in a given security level cannot write information to
a lower security level. The simple security rule is referred to as the “no read up” rule, and the *-property rule is
referred to as the “no write down” rule.
The third rule, the strong star property rule, states that a subject that has read and write capabilities can only
perform those functions at the same security level; nothing higher and nothing lower. So, for a subject to be
able to read and write to an object, the clearance and classification must be equal.If you are NOT making use of the strong star property, then there is no rule preventing you from writing up.
Incorrect Answers:
A: The simple security rule, referred to as the “no read up” rule, will prevent you from reading up.
B: The Bell-LaPadula model does not address covert channels.
C: The Bell-LaPadula model does not address management of access controls.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, pp. 369-370