Under Argentine law, when are emergency vehicle drivers (ambulances, fire engines, police - Clase D.4) legally exempt from general speed limits and traffic signals?

1. At all times, even when returning from off-duty personal errands
2. Exclusively when responding to a genuine emergency in active service with both acoustic sirens and optical emergency beacons activated, exercising extreme caution without endangering third parties
3. Whenever the driver is in uniform regardless of vehicle emergency equipment
4. Only on weekends and national holidays