Which category of bus according to UNECE Regulation 107 / Austrian KFG classification is legally permitted to transport standing passengers (Stehplätze) on scheduled public routes?

1. Class III (long-distance touring coaches exclusively with seated passengers)
2. Class I (urban low-floor transit buses with large standing areas) and Class II (interurban buses designed primarily for seated passengers but authorized for standing passengers on short-haul routes)
3. Class B (small mini-coaches under 22 passengers designed exclusively for seated tourists)
4. No bus in Austria may ever carry standing passengers under any circumstances