Question: In a USIM's Local Key Establishment security context (Key Availability Check mode), what is the outcome if a valid Ks_local key is not available for the received Ks_local identifier?
Option 1: The USIM generates a new Ks_local key and returns a successful Key Availability Check operation response.
Option 2: The command fails, and the status word '6A88' (Referenced data not found) is returned to indicate the absence of a valid Ks_local key.
Option 3: The USIM switches to an alternative security context to attempt the key availability check again.
Option 4: The operation times out, prompting a retransmission of the Local Key Establishment Mode command.
Explanation: In the context of USIM operations for Local Key Establishment (Key Availability Check mode), if the USIM cannot find a valid Ks_local key matching the received identifier, the operation is unsuccessful. When no valid Ks_local key is available, the command fails and returns a specific status word indicating that the referenced data was not found, aligning with standard practices in secure communication protocols.