What does a circular white sign with a red border containing '7.5 t' inside a vehicle outline indicate (Znak II-24, 'ograničenje ukupne mase vozila')?

1. Prohibition of all vehicles whose total actual mass (gross weight) exceeds 7.5 tonnes (Zabrana saobraćaja za vozila čija ukupna masa prelazi određenu masu)
2. Minimum required weight of 7.5 tonnes
3. Mandatory payload capacity of 7.5 tonnes
4. Axle load limit of 7.5 tonnes