Question: For a User Equipment (UE) supporting any ue-Category-NB, what is the requirement for NRS presence on non-anchor paging carriers in FDD mode as per E-UTRA specifications?
Option 1: Mandatory support as specified in E-UTRA physical channels and modulation standards.
Option 2: Optional support only if the UE operates exclusively in TDD mode.
Option 3: Conditional support based on the presence of specific UE radio access capabilities.
Option 4: Optional support as specified for UEs that support any ue-Category-NB.
Explanation: The correct answer is Option 4 because, according to the E-UTRA specifications (referencing TS 36.211 for physical channels and modulation), it is explicitly stated that NRS presence on non-anchor paging carriers for FDD is optional for UEs that support any ue-Category-NB. This highlights the flexibility in UE design for certain categories while ensuring compatibility with network configurations.