Question: What is excluded from the Error Number of DL TBs measurement in a cell?
Option 1: HARQ retransmissions
Option 2: NACK messages from UE
Option 3: Packet switched traffic
Option 4: CC transmissions
Explanation: The correct answer is Option 1 because the Error Number of DL TBs measurement excludes HARQ retransmissions, as stated in the text. This means that only initial transmissions are considered for this measurement, and any subsequent retransmissions due to errors are not included.