Question: In a 5G NR setup with Split Control and Data (SCG) configuration, how does a User Equipment (UE) interpret the term 'primary cell' when applying Physical Uplink Control Channel (PUCCH) procedures for the Secondary Cell Group (SCG)?
Option 1: The UE refers to the Master Cell Group's (MCG) Primary Cell as the 'primary cell'.
Option 2: The UE refers to the Primary Serving Cell (PSCell) of the SCG as the 'primary cell'.
Option 3: The UE selects the cell with the strongest signal between MCG and SCG as the 'primary cell'.
Option 4: The term 'primary cell' is not applicable for SCG configurations.
Explanation: According to the provided context, when procedures are applied for the SCG, the term 'primary cell' specifically refers to the Primary Serving Cell (PSCell) of the SCG. This distinction is crucial for correctly applying PUCCH procedures in a split control and data architecture, ensuring proper communication between the UE and the network regarding uplink control information for the secondary cell group.