= Solution
The <Bell-LaPadula model> protects <information confidentiality> by controlling information flow between security levels. Its <simple security property> says that a subject may read only objects whose classification does not exceed its maximum clearance:
$$
f_O(o)\le f_S(s).
$$
Thus a user cleared for confidential material cannot directly read a secret file. A <readwrite> permission includes reading and must satisfy the same restriction. This is an <access control> rule about who can learn existing contents; it says nothing by itself about where a cleared subject can subsequently copy them.
$$
\boxed{\text{The ss-property enforces confidentiality: no reading above maximum clearance.}}
$$
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