Under the special Slovak Category B rule, when may a B holder drive certain alternative-fuel goods vehicles up to 4,250 kg in Slovakia?

1. After two years from Category B entitlement, if the excess mass is due to the alternative-fuel propulsion system and load capacity is not increased
2. Immediately after passing the theory test only
3. Only if the driver is under 18
4. Only when towing a trailer over 750 kg