Question: What cause value would Node B use to reject a SYSTEM INFORMATION UPDATE REQUEST if it contains an IB SG REP IE or IB SG POS IE for an IB already in the BCCH schedule with the same IB Type and IB OC ID, but without prior deletion request?
Option 1: BCCH scheduling error
Option 2: SIB origination in Node B not supported
Option 3: BCH mapped on SCCPCH scheduling error
Option 4: Invalid IE repetition pattern
Explanation: This is because the Node B rejects updates with a "BCCH scheduling error" cause when an IB SG REP IE or IB SG POS IE indicates addition of an IB that already exists in the BCCH schedule (with same IB Type and IB OC ID) without a preceding deletion request, as per the specified abnormal condition handling rules.