Question: What happens if a UE has an Access Restriction for Unlicensed Spectrum in the form of LAA, LWA/LWIP, or NR-U when attempting to establish dual connectivity or carrier aggregation with LTE in unlicensed spectrum?
Option 1: The eNodeB ignores the restriction and establishes dual connectivity or carrier aggregation anyway.
Option 2: The eNodeB checks the restriction and only allows the UE to use licensed spectrum.
Option 3: The MME signals the restriction to the E-UTRAN, but it's up to the eNodeB to decide whether to honor it.
Option 4: The UE is automatically redirected to a different RAT that doesn't use unlicensed spectrum.
Explanation: According to the text, if the UE has an Access Restriction for Unlicensed Spectrum, the MME signals this to the E-UTRAN. The eNodeB then checks whether the UE is allowed to use unlicensed spectrum and shall not establish dual connectivity or carrier aggregation with LTE in unlicensed spectrum if the UE is not allowed to use it. This ensures that the UE only uses licensed spectrum when restricted from using unlicensed spectrum.