For which of the following purposes is the AccessController class used?

To determine most of the parameters of the Java sandbox and whether particular operations should be permitted or rejected.

To decide whether an access to a critical system resource is to be allowed or denied, based on the security policy currently in effect.

To mark code as being "privileged", thus affecting subsequent access determinations.

To obtain a "snapshot" of the current calling context so that access-control decisions from a different context can be made with respect to the saved context.