Question: What condition must be fulfilled for a UE to consider the entering condition for Event B1 (Inter RAT neighbour becomes better than threshold) satisfied?
Option 1: Mn + Ofn + Ocn - Hys < Thresh
Option 2: Mn + Ofn + Ocn + Hys > Thresh
Option 3: Mn + Ofn - Ocn - Hys > Thresh
Option 4: Mn + Ofn + Ocn - Hys > Thresh
Explanation: According to the 3GPP specification, the entering condition for Event B1 is satisfied when Inequality B1-1 (Mn + Ofn + Ocn – Hys > Thresh) is fulfilled. This means that the UE must consider the measurement result of the inter-RAT neighbour cell, taking into account any offsets and hysteresis, to be greater than the threshold for the event to be triggered.