Question: What happens to the F1 connection of a collocated IAB-DU when an IAB-MT enters the RRC INACTIVE state?
Option 1: The F1 connection is always released.
Option 2: The F1 connection is always kept.
Option 3: It is up to implementation to decide whether to keep or release the F1 connection.
Option 4: The IAB-MT does not support the RRC INACTIVE state.
Explanation: According to the general principles and procedures, when an IAB-MT enters the RRC INACTIVE state, it is up to implementation to decide whether to keep or release the F1 connection of the collocated IAB-DU. This means that there is no fixed rule for this scenario, and different implementations may handle it differently.