Question: What is the primary function of the gNB-DU in an IAB-node?
Option 1: To control the IAB-node's backhaul link via the F1 interface.
Option 2: To provide NR Uu access to UEs and child IAB-nodes.
Option 3: To manage the OAM system connection for the IAB-UE.
Option 4: To perform relaying at layer-3 for the IAB-node.
Explanation: The gNB-DU in the IAB-node is responsible for providing NR Uu access to UEs and child IAB-nodes, as stated in the text. This function allows the IAB-node to appear as a normal gNB to UEs and other IAB-nodes, enabling them to connect to the 5GC.