In the logs, it will tell you what type of trigger was activated and looking at that against what the last message was for the sensor is the only way to discern which notification was triggered.
For example, if your log says that a Threshold Trigger was activated and the last message from the sensor says that the "Sensor is below the 90% threshold", and you have a threshold trigger that says at 90% notify, then you know which notification was triggered.
Also, in the log, you can see the IDs for the notifications that were triggered. i.e. State Trigger sending EXE (Sensor/Source/ID: 2894/2894/3) the last number "3" is the ID of the trigger that was activated. If you search in the logs, it's possible to see what triggers have what IDs from when they were created or edited.