During a pre-trip inspection, you discover that one of the rear identification lights (the three red lights at the top rear of the trailer) is burned out. What action should you take?

1. It is acceptable to drive since the other two identification lights are still working
2. Replace the bulb or have it repaired before driving, as all required lights must be operational
3. Cover the burned-out light with red tape to simulate the light
4. Identification lights are optional on trailers and do not need to be working